Contents CHAPTER 18 ................................................................................................................................. 667

Use of Force .............................................................................................................................. 667

A. GENERAL ............................................................................................................................... 667

1. January U.S. Air Strike in Iraq ......................................................................................... 667

2. Other Actions in Response to Iran .................................................................................. 675

3. Bilateral and Multilateral Agreements and Arrangements ............................................. 677

a. North Macedonia Accession to NATO ......................................................................... 677

b. Status of Forces Agreement with Trinidad and Tobago .............................................. 677

c. Agreement with Supreme Headquarters Allied Powers Europe .................................. 678

d. Status of Forces Agreement with Antigua and Barbuda ............................................. 678

e. Greece Mutual Defense Cooperation Agreement ....................................................... 678

f. Defense Agreement with the Netherlands on personnel in the Caribbean .................. 678

g. Rwanda Status of Forces Agreement .......................................................................... 678

h. Poland Enhanced Defense Cooperation Agreement .................................................... 678

i. U.S.-Netherlands Defense Agreement......................................................................... 680

j. Guatemala Status of Forces Agreement ..................................................................... 680

4. International Humanitarian Law .................................................................................... 680

a. UN Security Council resolution on humanitarian access in the DRC ........................... 680

b. Applicability of international law to conflicts in cyberspace ....................................... 681

B. CONVENTIONAL WEAPONS .................................................................................................. 687

Lethal Autonomous Weapons Systems (“LAWS”) ................................................................. 687

C. DETAINEES ............................................................................................................................ 700

Al Qahtani v. Trump ........................................................................................................... 700

Cross References ...................................................................................................................... 703

667

CHAPTER 18

Use of Force

A. GENERAL

1. January U.S. Air Strike in Iraq

On January 8, 2020, U.S. Permanent Representative to the UN Kelly Craft provided a letter to the president of the Security Council, in accordance with Article 51 of the UN Charter reporting the actions taken in self-defense. U.N. Doc. No. S/2020/20. The body of the letter follows.

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* * * * In accordance with Article 51 of the Charter of the United Nations, I wish to report, on behalf of

my Government, that the United States has undertaken certain actions in the exercise of its

inherent right of self-defence. These actions were in response to an escalating series of armed

attacks in recent months by the Islamic Republic of Iran and Iran-supported militias on United

States forces and interests in the Middle East region, in order to deter the Islamic Republic of

Iran from conducting or supporting further attacks against the United States or United States

interests, and to degrade the Islamic Republic of Iran and Islamic Revolutionary Guard Corps

Qods Force-supported militias’ ability to conduct attacks. These actions include an operation on

2 January 2020 against leadership elements of Iran’s Islamic Revolutionary Guard Corps Qods

Force on the territory of Iraq. The United States is prepared to take additional actions in the

region as necessary to continue to protect United States personnel and interests.

Over the past several months, the United States has been the target of a series of

escalating threats and armed attacks by the Islamic Republic of Iran. These have included a

threat to the amphibious ship USS Boxer on 18 July 2019, while the ship was conducting a

planned inbound transit of the Strait of Hormuz, by an Iranian unmanned aerial system, which

was previously reported to the Council, as well as an armed attack on 19 June 2019 by an Iranian

surface-to-air missile on an unmanned United States Navy MQ-4 surveillance aircraft on a

routine surveillance mission monitoring the Strait of Hormuz in international airspace. The

actions taken by the United States occurred in the context of continuing armed attacks by the

Islamic Republic of Iran that have endangered international peace and security, including attacks

on commercial vessels off the port of Fujayrah and in the Gulf of Oman that threaten freedom of

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navigation and the security of international commerce, and missile and unmanned aircraft attacks

on the territory of Saudi Arabia.

Additionally, Qods Force-backed militias have engaged in a series of attacks against

United States forces. Qods Force-backed militia groups in Iraq, including Kata’ib Hizballah,

have conducted a series of indirect fire attacks targeting bases where United States forces in Iraq

are located. On 27 December 2019, one such attack resulted in the death of a United States

Government contractor and injury to four United States service members, all of whom were

present in Iraq with the consent and at the request of the Iraqi Government for counter-ISIS

operations notified to the Council in the United States letter dated 23 September 2014. In

immediate response to this 27 December attack, the United States struck five targets associated

with Kata’ib Hizballah in Iraq and Syria on 29 December 2019. Kata’ib Hizballah and other

Qods Force-backed militias then participated in an attack on the United States Embassy in

Baghdad on 31 December 2019, which resulted in significant damage to Embassy property.

Since our response, Iran on 7 January launched more than a dozen ballistic missiles

against United States military and coalition forces in Iraq. It is clear that these missiles were

launched from Iran and targeted at least two Iraqi military bases hosting United States military

and coalition personnel at Al-Asad and Erbil.

The United States wishes to note—as it has done repeatedly over the past years—that we

remain committed to a diplomatic resolution. We stand ready to engage without preconditions in

serious negotiations with Iran, with the goal of preventing further endangerment of international

peace and security or escalation by the Iranian regime.

* * * * On March 4, 2020, the general counsel for the U.S. Department of Defense, Paul

C. Ney, Jr., delivered remarks at Brigham Young University Law School, entitled “Legal Considerations Related to the U.S. Air Strike Against Qassem Soleimani.” The remarks are excerpted below and available at https://www.defense.gov/Newsroom/Speeches/Speech/Article/2181868/dod-general-counsel-remarks-at-byu-/#:~:text=Paul%20C.,Law%20School%20in%20Provo%2C%20Utah.

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* * * *

… On January 2, 2020, at the direction of the President of the United States, the U.S. military

conducted an air strike in Iraq targeting Qassem Soleimani, a major general in the Islamic

Revolutionary Guard Corps of Iran, and the commander of an expeditionary Revolutionary

Guards unit called the Qods Force. Among others also killed in the strike was Abu Mahdi al-

Muhandis, the leader of Kata’ib Hizballah, also known as KH, a Qods Force-backed Shia militia

in Iraq.

President Trump directed the strike on Soleimani in response to an escalating series of

attacks in preceding months by Iran and Iran-backed militias, including KH, against U.S. forces

and interests in the Middle East region. The strike was ordered to protect U.S. personnel; to deter

Iran from conducting or supporting further attacks on U.S. forces and interests; to degrade Iran’s

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and Qods Force-backed militias’ ability to conduct attacks; and to end Iran’s strategic escalation

of attacks on U.S. interests.

My aim today is to explain the international and domestic law underpinnings of the

January 2nd air strike. Much of what I will explain is reflected in publicly available documents

that the U.S. Government has already provided to the United Nations Security Council and to

Congress. The key legal conclusions are already a matter of record.

In the Pentagon, we always begin with the Bottom Line Up Front or B-L-U-F. Here’s the

BLUF for my remarks today. First, with respect to international law, the President directed the

January 2, 2020, air strike against Soleimani as an exercise of the United States’ inherent right to

act in self-defense, consistent with Article 51 of the Charter of the United Nations and customary

international law. Second, as to U.S. domestic law, the President had legal authority to order the

strike against Soleimani pursuant to his Article II constitutional power as Commander-in Chief

to use armed force to protect U.S. personnel and property in Iraq and U.S. interests in the Middle

East, and also pursuant to statutory authority under the 2002 Authorization for Use of Military

Force (AUMF) to “defend the national security of the United States against the continuing threat

posed by Iraq.”

I hope that by explaining how international law and U.S. domestic law applied to the

facts surrounding that operation, you will understand better why the strike on Soleimani was

lawful.

* * * *

Although the threat posed by Saddam Hussein’s regime was the initial focus of the

statute, the United States has relied upon the 2002 AUMF to authorize the use of force for the

purpose of establishing a stable, democratic Iraq and addressing terrorist threats emanating from

Iraq, even after Saddam Hussein’s demise.

Additionally, from 2003 to 2008, as sectarian violence erupted with the fall of the former

Ba’athist regime, President Bush directed a campaign against al-Qa’ida in Iraq pursuant to the

2001 Authorization for Use of Military Force or “2001 AUMF,” authorizing the use of force

against groups like al-Qa’ida—the “organization” responsible for the terrorist attacks of

September 11, 2001. In 2014, al-Qa’ida’s Iraq faction split from al-Qa’ida’s core leadership and

became the Islamic State of Iraq and Syria, or ISIS.

As Iraq became more stable, the United States and Iraq signed a cooperation agreement

in November 2008 that included defense and security related commitments and a recognition of

the importance of cooperation to “improve and strengthen security and stability in Iraq and the

region.” The two countries also signed an agreement providing for the withdrawal of U.S.

military personnel from Iraq by the end of 2011.

* * * *

U.S. forces, Iraqi Security Forces, and forces from countries participating in the Global

Coalition to Defeat ISIS (or D-ISIS) together fought to reverse ISIS’s conquests in Iraq and

helped liberate the Iraqi people from ISIS’s brutal control. Today, 100 percent of the territory

ISIS once held in Iraq has been returned to Iraqi government control. But despite the defeat of

ISIS’s control of territory in Iraq, ISIS remains a threat, and so U.S. forces have remained in Iraq

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to support Iraqi forces and ensure the enduring defeat of ISIS. There are presently more than

5,000 U.S. military personnel in Iraq.

As the United States has sought to establish stability in Iraq and to address terrorist

threats in and emanating from Iraq, Iran has remained a malign presence there and throughout

the Middle East. According to the Defense Intelligence Agency, Iran remains “implacably

opposed” to the United States, the U.S. presence in the Middle East, and U.S. support for certain

governments in the region, all of which Iran views as threats to its goals of regime survival and

regional dominance.

To achieve these goals, Iran typically uses “unconventional warfare elements and

asymmetric capabilities,” including “a complex network of State and non-State partners and

militant proxies” in the Middle East. The Islamic Revolutionary Guard Corps Qods Force is

Iran’s “primary tool” for conducting unconventional warfare and providing support to its foreign

partners and proxies like Hizballah, Hamas, and the Houthis.

* * * *

Qassem Soleimani had commanded the Qods Force beginning in the late 1990s and

orchestrated the group’s ascendance. He was the lead architect behind Iran’s campaign of

terrorism, assassinations, arms-smuggling, and violence throughout the Middle East, including

against U.S. personnel in Iraq. Soleimani’s malign activities have not been limited to the Middle

East. In 2011, Soleimani supervised a Qods Force plot to assassinate Saudi Arabia’s Ambassador

to the United States with explosives at a Washington, D.C. restaurant. … In April 2019, the

United States designated the Islamic Revolutionary Guard Corps, “including the Qods Force,” as

a foreign terrorist organization, citing, among other things, the Qods Force’s support for terrorist

groups and plots in the United States, Europe, Africa, and the Middle East.

In the months preceding the January 2nd air strike against Soleimani, Iran and Iran-

supported militias had engaged in a series of attacks against U.S. personnel and property in Iraq

and against U.S. interests and Allies and partners in the Middle East. In June 2019, an Iranian

surface-to-air missile destroyed an unmanned U.S. Navy surveillance aircraft while it was on a

routine mission in international airspace monitoring the Strait of Hormuz.

The U.S. response to the attack at that time was measured and muted, but Iran continued

its pattern of aggression against U.S. interests in the region. In July 2019, USS Boxer, an

amphibious assault ship, came under threat from Iranian unmanned aerial systems while

conducting a planned transit of the Strait of Hormuz. Iran has also attacked and seized

commercial ships in the area, threatening freedom of navigation. And, Iran-backed Houthi rebels

in Yemen shot down two U.S. unmanned surveillance aircraft in Yemeni airspace and conducted

multiple missile and other attacks in Saudi Arabia targeting airports and other civilian facilities.

Moreover, on September 14, 2019, Iran launched a devastating air attack on a gas plant and an

oil refinery in Saudi Arabia.

In the weeks preceding the air strike against Soleimani, provocations against the United

States intensified with a series of attacks by Iran-supported militias on U.S. personnel and

property in Iraq. KH, the Qods Force-backed Shia militia group, fired rockets at bases in Iraq

where U.S. forces are located. Between November 9 and December 9, 2019, Qods Force-backed

militia groups fired rockets at the Qayyarah West Air Base, Al Asad Air Base, and the Baghdad

Embassy complex. Then, on December 27, KH attacked the K-1 Air Base in Kirkuk, killing a

U.S. contractor and injuring U.S. and Iraqi military personnel. In response, U.S. forces struck a

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number of KH installations in Iraq and Syria to degrade the group’s ability to launch additional

attacks. Then, on December 31, KH and other Iran-backed militia groups organized a

demonstration that turned violent at the U.S. Embassy in Baghdad, inflicting significant damage

to U.S. property and imperiling U.S. lives.

* * * *

First, let’s talk about international law.

The U.N. Charter generally prohibits States from resorting to the use of force against

another State without a legal basis. This rule is part of the law governing the resort to force, or, to

use the Latin term, jus ad bellum. The United States recognizes three circumstances in which a

resort to force in a foreign country is not generally prohibited under international law: (1) use of

force authorized by the U.N. Security Council acting under the authority of Chapter VII of the

U.N. Charter; (2) use of force in the exercise of the inherent right of self-defense; and (3) use of

force in an otherwise lawful manner with the consent of the territorial State.

The strike targeting Soleimani in Iraq was taken under the second justification I

mentioned – in U.S. self-defense – consistent with Article 51 of the U.N. Charter. Article 51

provides in relevant part that: “Nothing in the present Charter shall impair the inherent right of

individual or collective self-defense if an armed attack occurs against a Member of the United

Nations . . . .”

Article 51 thus recognizes the inherent right of States to resort to force in individual or

collective self-defense against an armed attack. In accordance with Article 51, the United States

reported the air strike to the UN Security Council on January 8, 2020, in written correspondence

from the U.S. Ambassador to the United Nations, Kelly Craft, to the other members of the

Security Council, through the President of the Security Council.

The use of force in self-defense is subject to the customary international law

requirements of necessity and proportionality.

As the DoD Law of War Manual explains, “[t]he jus ad bellum condition of necessity

requires that no reasonable alternative means of redress are available. For example, in exercising

the right of self-defense, diplomatic means must be exhausted or provide no reasonable prospect

of stopping the armed attack or threat thereof.”

Applying this legal standard to the facts which I just described, the United States had

been subject to an escalating series of armed attacks by Iran and by Iran-supported militias in the

Middle East, including Iraq. This included the threat to USS Boxer by Iranian unmanned aerial

systems and an armed attack by an Iranian surface-to-air missile on an unmanned U.S. Navy

MQ-4 surveillance aircraft in international airspace in the Persian Gulf region. And the strike

against Soleimani occurred in the larger context of continuing armed attacks by Iran that

endangered international peace and security, attacks on commercial vessels in the Gulf of Oman,

attacks on the territory of Saudi Arabia, and attacks by Qods Force-backed militias against U.S.

forces in the previous several months. Although I cannot speak to the classified information that

senior leaders reviewed, I hope you can see, based simply on these facts that are publicly known,

why our senior leaders and the President were reasonable in believing that the use of force was

necessary. Attacks against U.S. forces and interests were assessed to be highly likely to continue

in the absence of a military response in self-defense to restore deterrence.

Moreover, the strike on January 2d was also consistent with the international law

requirement that our measures in self-defense be “proportionate to the nature of the threat being

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addressed.” As DoD communicated to the public at the time, “General Soleimani was actively

developing plans to attack American diplomats and service members in Iraq and throughout the

region.” “He had orchestrated attacks on coalition bases in Iraq over the last several months,”

and he also approved the demonstration that turned violent at the U.S. Embassy in Baghdad just

two days earlier on December 31. Targeting the Iranian commander responsible for

orchestrating, planning, and supporting recent attacks against the United States and planning new

attacks was a proportionate response to the threat of such attacks.

Some have questioned whether another Iranian armed attack against the United States

was “imminent” at the time of the strike targeting Soleimani. This is a red herring, as the saying

goes. Under international law, an imminent attack is not a necessary condition for resort to force

in self-defense in this circumstance because armed attacks by Iran already had occurred and were

expected to occur again.

Of course, although such analysis was not necessary in this case given this recent history

of past attacks, the threat of an imminent armed attack can also justify a resort to force under

international law. That is, although Article 51 refers explicitly to self-defense only in response to

an actual armed attack, the United States maintains that international law also includes the right

to use force where an armed attack is imminent. This view of the United States is widely known

and also shared by many like-minded states in the international community.

In addition to regulating the resort to force, international law also regulates the conduct of

hostilities. The law of war requires, for example, that attacks be directed against military

objectives, that precautions be taken to reduce the likelihood of civilian casualties, and that any

damage caused be proportionate to the military objective. The law of war does not prohibit

targeting specifically identified leaders of adversary militaries—they may be made the object of

attack as enemy combatants.

As the leader of the Qods Force, Soleimani was a legitimate military target in Iraq under

the international law governing the conduct of hostilities. The others killed in the U.S. strike

were the leader and members of KH, an Iran-backed militia. As such, they, too, were “military

objectives” who could be made the object of attack under the law of war.

To sum up, the January 2, 2020, air strike against Soleimani in Iraq was lawful as a

matter of international law as an exercise of the inherent right of self-defense recognized by

Article 51 of the U.N. Charter. An imminent attack is not a necessary condition for use of force

in self-defense under Article 51 when an armed attack has already been perpetrated and the

response is necessary and proportionate.

Let me turn now to a discussion of the legal basis for the strike under U.S. domestic law.

The use of military force requires a basis in domestic law. The President may rely on

congressional authorizations for the use of force – such as the 2001 AUMF and the 2002 AUMF

– and the President may rely on Article II constitutional authority. In the absence of statutory

authorization, the President’s constitutional authority to direct military action can be distilled

into two inquiries. First, whether the President could reasonably determine that the action serves

important national interests. Second, whether the “anticipated nature, scope and duration” of the

conflict might rise to the level of a war under the Constitution.

Applying this domestic law framework to the circumstances of the strike targeting

Soleimani, the President had a sufficient legal basis both under his constitutional authority and

pursuant to the statutory authority of the 2002 AUMF.

First, with respect to the question of the President’s constitutional authority to order the

strike, the important national interest to prevent or respond to attacks on U.S. personnel and

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property is at the very heart of his constitutional power as Chief Executive and Commander-in-

Chief. Past Presidents have used force specifically in response to attacks on U.S. embassies and

personnel, including by State actors abroad. For instance, in April 1986, President Reagan

directed air strikes against the Libyan leader Qaddafi and his intelligence services in Libya

following terrorist attacks that killed and wounded American soldiers and civilians at a

discotheque in Germany. And in June 1993, President Clinton ordered the launch of cruise

missiles on Iraqi Intelligence Headquarters based on “compelling evidence” that Iraqi

intelligence had tried to assassinate former President George H.W. Bush in Kuwait. President

Clinton also ordered air strikes in August 1998 against Usama bin Laden and al-Qa’ida in

Afghanistan and Sudan, in response to al-Qa’ida bombings of the U.S. Embassies in Nairobi and

Dar es Salaam, which had killed more than 250 persons.

Let’s turn now to the second constitutional law inquiry: whether the air strike on

Soleimani presented a sufficient risk of broadened conflict with Iran such that pre-approval by

Congress may have been required. Although the Constitution vests in the President independent

authority to use force, it reserves to Congress the power to “declare War” and the authority to

fund military operations. This was a deliberate choice of the Founders. In the Federalist Papers,

for example, Alexander Hamilton noted that the President lacks the authority of the British King,

which “extends to the declaring of war and … the raising and regulating of fleets and armies.”

For that reason, the President’s decision to use armed force cannot be sustained over time

without the acquiescence, indeed the approval, of Congress, for it is Congress that must

appropriate the money to fight a war. The Department of Justice’s Office of Legal Counsel

(OLC) has similarly recognized that the President should seek congressional approval prior to

initiating military action that would bring the Nation into the kind of protracted conflict that

would rise to the level of a “war” in the constitutional sense.

So what does a “war” in the constitutional sense mean? The relevant Department of

Justice OLC opinions say that we must engage in a “fact-specific assessment of the ‘anticipated

nature, scope, and duration’ of the planned military operations.” Under this standard, military

operations may rise to the level of “war” in the constitutional sense when the actions are likely to

lead to “prolonged and substantial military engagements, typically involving exposure of U.S.

military personnel to significant risk over a substantial period.” Some of the most relevant facts

in this analysis would include the numbers of additional forces to be deployed, the quantity of

munitions expended, estimates regarding U.S. and enemy casualties, and whether ground forces

are to be deployed into a war zone. Making an assessment of the anticipated nature, scope, and

duration of planned military operations is one of those judgments that are, as Justice Jackson

described, “delicate, complex, and involve large elements of prophecy,” which have traditionally

been committed to the Executive branch, given its military, diplomatic, and intelligence

resources.

The strike against Soleimani did not involve a substantial military engagement, the

deployment of additional U.S. forces, or the risk of significant casualties. The operation was

circumscribed: it consisted of one targeted air strike in Iraq, executed by an unmanned aerial

vehicle, designed to avoid civilian casualties or substantial collateral damage, and intended to

prevent future attacks against U.S. persons and interests in Iraq and throughout the region. It was

not “aim[ed] at the conquest or occupation of territory nor . . . at imposing through military

means a change in the character of a political régime.”

At the same time, there existed risk that the operation could escalate into a broader

conflict. Although Soleimani and the Qods Force were not a conventional military formation, the

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Qods Forces is a part of the military of Iran, which has significant armed forces and military

assets that could respond with armed force.

However, the President decided based upon available intelligence that the targeted

operation would be unlikely to escalate into a full-scale war, and that, by restoring deterrence of

further attacks orchestrated by the Qods Force, the strike could in fact result in a de-escalation of

the conflict between the United States and Iran. As the President himself said, the strike on

Soleimani was taken to stop a war, not to start one. Indeed, the United States government made

clear immediately after the January 2d air strike—as it had planned to do before launching the

operation— that the strike reflected a limited engagement and that the United States did not seek

a broader war with Iran.

Subsequent events appear to have confirmed the reasonableness of the assessment that

the strike would not provoke an uncontrolled escalation. On January 7, 2020, Iran responded to

the strike on Soleimani by firing ballistic missiles at U.S. military and coalition forces at two

bases in Iraq. But the United States did not itself respond to this new attack with further air

strikes, although it took precautions to minimize casualties and damages. Immediately after the

missile attacks, Iran’s foreign minister, Javad Zarif, asserted that his country “took and

concluded proportionate measures” in response to the targeting of Soleimani, adding that Iran

“do[es] not seek escalation or war.”

In sum, given the narrow scope of the mission, the available intelligence, and the efforts

to avoid escalation, it was reasonable for the President to have determined that the nature, scope,

and duration of hostilities directly resulting from the strike against Soleimani in Iraq would not

rise to the level of war with Iran for constitutional purposes.

Although the President had constitutional authority under Article II to direct the January

2nd air strike, he also had statutory authority under the 2002 AUMF. Pursuant to the 2002

AUMF, Congress has authorized the President “to use the Armed Forces of the United States as

he determines to be necessary and appropriate in order to . . . defend the national security of the

United States against the continuing threat posed by Iraq.” As I mentioned earlier, although the

threat posed by Saddam Hussein’s regime was the initial focus of the 2002 AUMF, the United

States has relied consistently upon the 2002 AUMF to authorize the use of force for the purpose

of establishing a stable, democratic Iraq and addressing terrorist threats emanating from Iraq

under the George W. Bush, Obama, and Trump Administrations. Such uses of force need not

only address threats from the Iraqi Government apparatus but may also address threats to the

United States posed by militias, terrorist groups, or other armed groups in Iraq. For example, the

Obama Administration invoked the 2002 AUMF (along with the 2001 AUMF) as domestic legal

authority for conducting military operations against ISIS in Iraq and also operations in Syria to

address threats emanating from Iraq.

The air strike against Soleimani in Iraq is consistent with this longstanding interpretation

of the President's authority under the 2002 AUMF. The use of force was tailored narrowly to

Soleimani’s presence in Iraq and his support to – including in some cases the direction of –

militias that attacked U.S. personnel and bases in Iraq. U.S. national security officials believed

that Soleimani was actively planning additional attacks on U.S. personnel in Iraq and in the

region. Soleimani, as the leader of the Qods Force directly orchestrating hostilities against U.S.

personnel and property in Iraq, was a necessary and appropriate target for the President to use

force against under the 2002 AUMF.

* * * *

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On July 9, 2020, the State Department issued a press statement by Secretary Pompeo rejecting the opinion of a UN special rapporteur related to the U.S. strike that killed Soleimani. The statement, available at https://2017-2021.state.gov/un-special-rapporteur-gives-more-cause-to-distrust-un-human-rights-mechanisms/, reaffirms the U.S. rationale for the strike:

… The strike that killed General Soleimani was in response to an escalating series of armed attacks in preceding months by the Islamic Republic of Iran and militias it supports on U.S. forces and interests in the Middle East region. It was conducted to deter Iran from launching or supporting further attacks against the United States or U.S. interests, and to degrade the capabilities of the Qods Force.

The United States is transparent regarding the international law basis for the strike. As we outlined in a January 8, 2020, letter to the UN Security Council submitted in accordance with Article 51 of the UN Charter, the strike was undertaken in the exercise of the United States’ inherent right of self-defense. …

2. Other Actions in Response to Iran On March 12, 2020, the U.S. Department of Defense issued a statement regarding the strikes conducted by U.S. forces against Kata’ib Hizbollah (“KH”) in Iraq. The statement is excerpted below and available at https://www.centcom.mil/MEDIA/STATEMENTS/Statements-View/Article/2110837/statement-by-the-department-of-defense/.

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* * * *

…These strikes targeted five weapon storage facilities to significantly degrade their ability to

conduct future attacks against Operation Inherent Resolve (OIR) coalition forces. These weapons

storage facilities include facilities that housed weapons used to target U.S. and coalition troops.

These strikes were defensive, proportional, and in direct response to the threat posed by

Iranian-backed Shia militia groups (SMG) who continue to attack bases hosting OIR coalition

forces.

Yesterday’s attack on Camp Taji killed two U.S. and one U.K. service members and

wounded 14 others. It marked the latest in a series of rocket attacks conducted by Iranian-backed

SMGs against U.S. and coalition personnel—killing five and wounding dozens more, including

Iraqi Security Forces.

“The United States will not tolerate attacks against our people, our interests, or our

allies,” Secretary of Defense Dr. Mark T. Esper said. “As we have demonstrated in recent

months, we will take any action necessary to protect our forces in Iraq and the region.”

During discussions with senior Iraqi officials, the department re-emphasized its

commitment to the force protection of coalition service members and to preventing SMG attacks

on coalition forces.

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These terror groups must cease their attacks on U.S. and coalition forces or face

consequences at a time and place of our choosing.

The U.S. and the coalition remain committed to the lasting defeat of ISIS, and the long-

term security, stability, and sovereignty of Iraq.

* * * *

On April 22, 2020, the State Department issued a fact sheet on Iran’s history of naval provocations. The fact sheet is excerpted below and available at https://2017-2021.state.gov/irans-history-of-naval-provocations/.

___________________

* * * *

Iran has long used its naval forces to terrorize the international maritime community… . In 2015,

during negotiations of the Iran Deal and after its adoption, the U.S. Navy recorded 22 incidents

of unsafe and unprofessional conduct by the IRGC Navy (IRGCN), many that risked collision.

An additional 36 incidents of unsafe and unprofessional conduct were recorded in 2016.

This includes the January 2016 incident where IRGC naval forces seized two U.S. Navy

riverine boats and detained ten U.S. sailors for a period of 15 hours, violating their rights under

the Geneva Convention by parading them in front of their propaganda cameras.

When President Trump took office, he initiated a comprehensive review of the United

States’ Iran policy in light of the Iran Deal’s failure to address the regime’s growing threats to

international peace and security. During this review period, Iran continued its dangerous naval

activity.

• In March 2017, the USNS Invincible was forced to change course to avoid collision with

multiple approaching IRGCN fast-attack small crafts.

• In July 2017, an IRGCN vessel came within 150 yards of the USS Thunderbolt in the

Persian Gulf, forcing it to fire warning shots.

• In August 2017, an unarmed Iranian drone flew close to the USS Nimitz as fighter jets

landed at night, threatening the safety of the American pilots and crew.

In October 2017, President Trump announced a new Iran policy that made clear the

United States would not tolerate the status quo from Iran, nor appease their provocations.

Following the President’s announcement, incidents of IRGC naval harassment sharply declined

and remained depressed even after the United States withdrew from the JCPOA.

In May 2019, Iran began a panicked campaign of aggression to extort the world into

granting it sanctions relief.

• On May 12, 2019, IRGC naval personnel placed and detonated limpet mines on two

Saudi, one UAE, and one Norwegian-registered ships while they were harbored in UAE

territorial waters near Fujairah Port.

• On June 13, 2019, IRGC naval personnel placed and detonated limpet mines on one

Japanese ship and one Norwegian owned ship while they transited the Gulf of Oman. The

U.S. later released a video showing IRGC naval personnel removing one of their limpet

mines off the side of the Japanese tanker.

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• On June 19, 2019, IRGC personnel deployed a surface-to-air missile to shoot down a

U.S. unmanned aircraft operating over international waters in the Strait of Hormuz. IRGC

Commander Hossein Salami announced that Iran had shot down the drone, claiming that

it was operating within Iran’s territorial waters.

• On July 19, 2019, the IRGC Navy seized the British-flagged, Swedish-owned Stena

Impero tanker while it was transiting the Strait of Hormuz. On the same day, the IRGC

also temporarily detained the Liberian-flagged Mesdar tanker. The Stena Impero and her

crew were detained in Iran for more than two months as negotiating leverage.

At the same time the Iranian regime is seeking sanctions relief, it focuses its resources

and efforts to harass the international maritime community.

• On April 14, 2020, the IRGC Navy forcibly boarded and detained the Hong Kong-

flagged SC Taipei oil tanker in international waters, and sailed the tanker into Iranian

waters.

• On April 15, 2020, eleven IRGC Navy small boats disrupted five U.S. naval vessels

conducting a routine exercise by repeatedly engaging in high speed, harassing

approaches. The Iranian vessels repeatedly crossed the bows and sterns of the U.S. ships

coming as close as to within 10 yards of a US Coast Guard Cutter.

In response to the elevated risk posed to commercial vessels transiting the Strait of

Hormuz, the United States spearheaded the creation of the International Maritime Security

Construct (IMSC), a coalition of eight European, Middle Eastern, and Asian nations committed

to ensuring freedom of navigation and the free flow of commerce through the strait. Since the

IMSC was stood up in August 2019, Iranian mine attacks have ceased.

President Trump will not tolerate or appease Iran’s foreign policy of violence and

intimidation. Iran must act like every other normal nation, not a nation that sponsors piracy and

terror.

* * * * 3. Bilateral and Multilateral Agreements and Arrangements

a. North Macedonia Accession to NATO

As discussed in Digest 2019 at 615, the Protocol to the North Atlantic Treaty on the Accession of the Republic of North Macedonia was signed and received U.S. Senate advice and consent to ratification in 2019. On March 27, 2020, North Macedonia deposited its instrument of accession with the United States as depositary. See State Department press statement, available at https://2017-2021.state.gov/north-macedonia-joins-the-nato-alliance/. North Macedonia acceded at the 30th member of NATO. The protocol is available at https://www.state.gov/20-319.

b. Status of Forces Agreement with Trinidad and Tobago On January 1, 2020, the extension of the U.S. status of forces agreement with Trinidad and Tobago entered into force via exchange of notes at Port of Spain on December 17,

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2019 and January 30, 2020. The agreement is available at https://www.state.gov/trinidad_and_tobago-20-101.

c. Agreement with Supreme Headquarters Allied Powers Europe The Agreement Between the United States and the Supreme Headquarters Allied Powers Europe (“SHAPE”) entered into force January 2, 2020 after an exchange of letters at Casteau October 18, 2019 and January 2, 2020. The agreement is available at https://www.state.gov/shape-20-102.

d. Status of Forces Agreement with Antigua and Barbuda On January 24, 2020 the U.S. status of forces agreement with Antigua and Barbuda entered into force. The agreement was signed at Washington on March 12, 2014. The text of the agreement is available at https://www.state.gov/antigua_and_barbuda-20-124.

e. Greece Mutual Defense Cooperation Agreement On February 13, 2020, the agreement amending and extending U.S. defense cooperation with Greece, which was signed at Athens on October 5, 2019, entered into force. The agreement is available at https://www.state.gov/greece-20-213. The original defense cooperation agreement from 1990 was previously extended every year from 1998, to 2017.

f. Defense Agreement with the Netherlands on personnel in the Caribbean The U.S.-Netherlands defense agreement on the status of U.S. personnel in the Caribbean part of the Kingdom of the Netherlands entered into force on April 22, 2020. The agreement was effected by an exchange of notes at The Hague in 2018 and extends the application of a previous 2012 agreement with the Netherlands to Curacao. The text of the agreement is available at https://www.state.gov/netherlands_20-422.

g. Rwanda Status of Forces Agreement

On May 28, 2020, the Status of Forces Agreement with Rwanda entered into force upon signature at Kigali. The agreement is available at https://www.state.gov/rwanda-20-528.

h. Poland Enhanced Defense Cooperation Agreement

On August 15, 2020, in Warsaw, the United States and Poland signed an enhanced defense cooperation agreement (“EDCA”). The State Department fact sheet on the

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EDCA is excerpted below and available at https://2017-2021.state.gov/u-s-poland-enhanced-defense-cooperation-agreement/. The EDCA entered into force on November 13, 2020 and is available at https://www.state.gov/poland-20-1113-enhanced-defense-cooperation-agreement/.

___________________

* * * *

The United States values our strong bilateral relationship with Poland. We look forward to

Poland’s swift ratification of the EDCA, which will permit us to implement fully the enhanced

defense cooperation [agreement]…

POLAND IS A CLOSE FRIEND OF THE UNITED STATES AND A LINCHPIN OF

REGIONAL SECURITY

• The U.S.-Poland relationship is strong and getting stronger. We are fellow democracies,

with a deep commitment to the rule of law, human rights, and individual freedom.

• Warsaw has been a strong NATO Ally since its accession to the Alliance in 1999, and

serves as a linchpin of regional security. Poland is a crucial strategic U.S. Ally in Central

Europe. Polish troops stand shoulder-to-shoulder with U.S. forces in Afghanistan and

elsewhere, and provide critical support to the Defeat-ISIS Campaign.

• The United States leads the enhanced Forward Presence battle group in Poland and

deploys a rotational Armored Brigade Combat Team under Operation Atlantic Resolve,

funded through the European Deterrence Initiative.

THE U.S.-POLAND EDCA PROVIDES THE LEGAL FRAMEWORK FOR OUR

COUNTRIES TO WORK TOGETHER

• The EDCA reflects the shared vision outlined in the joint declarations signed by

Presidents Trump and Duda in 2019, and reaffirmed during President Duda’s June 2020

visit to Washington, to deepen our defense cooperation.

• The EDCA supplements the 1951 NATO Status of Forces Agreement (SOFA) and

establishes a framework to enhance and modernize our capabilities, in support of the

NATO Alliance’s collective defense. The United States has similar agreements with other

NATO Allies such as Bulgaria, Hungary, and Romania.

• The EDCA outlines the legal status of U.S. forces in Poland and will provide the

necessary authorities for U.S. forces to access specific Polish military installations and

conduct activities for our mutual defense. This Agreement also supports expanded

infrastructure, and enables an increased U.S. military presence in Poland.

THE U.S.-POLAND EDCA WILL STRENGTHEN NATO AND INCREASE

TRANSATLANTIC SECURITY FOR DECADES TO COME

• The EDCA provides a mechanism for the sharing of logistical and infrastructure costs for

U.S. forces present in Poland. By creating a durable framework for even closer defense

cooperation with a crucial NATO Ally, it strengthens Eastern Flank security and

deterrence.

• Poland’s in-kind contributions under the EDCA will directly benefit the Polish economy.

For its part, the United States will continue to bear the costs of training, equipping, and

deploying U.S. forces to Poland, which is significantly higher than the cost of support

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Poland invests in support of U.S. forces once they are in country. Together, these efforts

improved security and stability for both nations in a cost-effective way.

• The United States and Poland’s extensive coordination and consultation on defense

cooperation matters will be strengthened and streamlined by the EDCA.

* * * *

i. U.S.-Netherlands Defense Agreement The Agreement between the United States of America and the Kingdom of the Netherlands Establishing a Framework for Defense Cooperation Activities was signed July 2, 2018 at Washington and entered into force November 1, 2020 with the exchange of correcting notes. The agreement is available at https://www.state.gov/netherlands-20-1101.

j. Guatemala Status of Forces Agreement The United States-Guatemala Status of Forces Agreement was effected by an exchange of notes at Guatemala November 25 and December 1, 2020 and entered into force December 1, 2020. The agreement is available at https://www.state.gov/guatemala-20-1201.

4. International Humanitarian Law

a. UN Security Council resolution on humanitarian access in the DRC On December 18, 2020, the United States submitted, for the record, an explanation of vote on a draft resolution on the UN Organization Stabilization Mission in the Democratic Republic of the Congo (“MONUSCO”). The statement reflects the U.S. view that requirements in UN Security Council resolutions that parties provide "safe, rapid, and unhindered" humanitarian access should not be combined with the phrase “in accordance with international law,” because "safe, rapid, and unhindered" humanitarian access is not a requirement of international law in all circumstances. The statement follows and is available at https://usun.usmission.gov/explanation-of-vote-on-a-draft-resolution-on-the-un-organization-stabilization-mission-in-the-democratic-republic-of-the-congo/..

* * * *

We further appreciate the Council’s efforts to support MONUSCO’s gradual and responsible

transition and note the importance of ensuring that the DRC government, UN country team, and

other actors are prepared to take over the mission’s important tasks, such as early warning alert

networks.

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However, we must clarify the U.S. position on the language in this resolution regarding

humanitarian access. The United States strongly supports the need for humanitarian access in

conflict areas, having backed language in numerous Security Council resolutions that demands

parties to a conflict provide safe, rapid, and unhindered access to humanitarian aid. Our words

are supported by our actions, as the United States has provided more funding for humanitarian

aid than any other country in the world — more than $10.5 billion last year.

Our concern in this resolution is related to changes made this year regarding how

international law is referred to in the humanitarian context. While the United States recognizes

that in certain circumstances States may have obligations related to humanitarian aid, there is no

universal and unlimited international legal obligation for States to allow and facilitate “safe,

rapid, and unhindered” humanitarian access. Therefore, the United States disagrees with the

insertion of the phrase “in accordance with international law” in paragraph 35 of this resolution,

where its placement suggests that safe, rapid, and unhindered humanitarian access is required by

international law without exception. Nonetheless, the United States remains a strong advocate, in

this Council and more generally, for States and parties to the conflict to allow and facilitate safe,

rapid, and unhindered humanitarian access. We invite other members of this Council to consult

with us regarding how we can maintain strong humanitarian access clauses in Security Council

resolutions while accurately capturing the law.

* * * *

b. Applicability of international law to conflicts in cyberspace On March 2, 2020, General Counsel Ney delivered remarks at the U.S. Cyber Command Legal Conference, addressing considerations for conducting legal reviews of U.S. military cyber operations. Mr. Ney’s remarks are excerpted below and available at https://www.defense.gov/Newsroom/Speeches/Speech/Article/2099378/dod-general-counsel-remarks-at-us-cyber-command-legal-conference/.

___________________

* * * *

I have two objectives today. First, I’ll offer a snapshot of how we in DoD are integrating

cyberspace into our overall national defense strategy. Second, I will summarize the domestic and

international law considerations that inform the legal reviews that DoD lawyers conduct as part

of the review and approval process for military cyber operations. We at DoD now have

considerable practice advising on such operations and are accordingly in a position to begin to

speak from experience to some of the challenging legal issues that cyber operations present.

To set the scene, when I talk about “cyberspace,” I am referring to “the interdependent

network of information technology infrastructures and resident data, including the Internet,

telecommunications networks, computer systems, and embedded processors and controllers.”

Physically, and logically, the domain is in a state of perpetual transformation. It enables the

transmission of data across international boundaries in nanoseconds—controlled much more by

individuals or even machines than by governments—spreading ideas to disparate audiences and,

in some cases, the generating of physical effects in far-flung places.

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1. Today’s Cyber Threat Environment and DoD’s Response

* * * *

2. Framework for Legal Analysis

To evaluate the legal sufficiency of a proposed military cyber operation, we employ a

process similar to the one we use to assess non-cyber operations. We engage our clients to

understand the relevant operational details: What is the military objective we seek to achieve?

What is the operational scheme of maneuver and how does it contribute to achieving that

objective? Where is the target located? Does the operation involve multiple geographic

locations? What is the target system used for? How will we access it? What effects—such as loss

of access to data—will we generate within that system? How will those effects impact the

system’s functioning? Which people or processes will be affected by anticipated changes to the

system’s functioning? Are any of those likely to be impacted civilians or public services?

Answers to these questions will drive the legal analysis.

A. U.S. Domestic Law

Let’s take up considerations of U.S. domestic law first. We begin with the foundational

question of domestic legal authority to conduct a military cyber operation. The domestic legal

authority for the DoD to conduct cyber operations is included in the broader authorities of the

President and the Secretary of Defense to conduct military operations in defense of the nation.

We assess whether a proposed cyber operation has been properly authorized using the analysis

we apply to all other operations, including those that constitute use of force. The President has

authority under Article II of the U.S. Constitution to direct the use of the Armed Forces to serve

important national interests, and it is the longstanding view of the Executive Branch that this

authority may include the use of armed force when the anticipated nature, scope, and duration of

the operations do not rise to the level of “war” under the Constitution, triggering Congress’s

power to declare war. Furthermore, the Supreme Court has long affirmed the President’s power

to use force in defense of the nation and federal persons, property, and instrumentalities.

Accordingly, the President has constitutional authority to order military cyber operations even if

they amount to use of force in defense of the United States. Of course, the vast majority of

military operations in cyberspace do not rise to the level of a use of force; but we begin analysis

of U.S. domestic law with the same starting point of identifying the legal authority.

In the context of cyber operations, the President does not need to rely solely on his

Article II powers because Congress has provided for ample authorization. As I noted earlier,

Congress has specifically affirmed the President’s authority to direct DoD to conduct military

operations in cyberspace. Moreover, cyber operations against specific targets are logically

encompassed within broad statutory authorizations to the President to use force, like the 2001

Authorization for the Use of Military Force, which authorizes the President to use “all necessary

and appropriate force” against those he determines were involved in the 9/11 attacks or that

harbored them. Congress has also expressed support for the conduct of military cyber operations

to defend the nation against Russian, Chinese, North Korean, and Iranian “active, systematic, and

ongoing campaigns of attacks” against U.S. interests, including attempts to influence U.S.

elections.

In addition to questions of legal authority, DoD lawyers advise on the Secretary of

Defense’s authority to direct the execution of military cyber operations as authorized by the

President and statute, “including in response to malicious cyber activity carried out against the

683 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

United States or a United States person by a foreign power,” and to conduct related intelligence

activities. Our lawyers ensure that U.S. military cyber operations adhere to the President’s

specific authorizations as well as the generally applicable NSPM-13.

After concluding that the operation has been properly authorized, DoD lawyers assess

whether there are any statutes that may restrict DoD’s ability to conduct the proposed cyber

operation and whether the operation may be carried out consistent with the protections afforded

to the privacy and civil liberties of U.S. persons. To illustrate, I am going to talk about two

statutes and the First Amendment as examples of laws that we may consider, depending on the

specific cyber operation to be conducted.

* * * *

B. International Law

Those are some highlights of U.S. domestic law considerations that may be implicated by

proposed military cyber operations; let me turn now to international law.

We recognize that State practice in cyberspace is evolving. As lawyers operating in this

area, we pay close attention to States’ explanations of their own practice, how they are applying

treaty rules and customary international law to State activities in cyberspace, and how States

address matters where the law is unsettled. DoD lawyers, and our clients, engage with our

counterparts in other U.S. Government departments and agencies on these issues, and with Allies

and partners at every level—from the halls of the United Nations to the floors of combined

tactical operations centers—to understand how we each apply international law to operations in

cyberspace. Initiatives by non-governmental groups like those that led to the Tallinn Manual can

be useful to consider, but they do not create new international law, which only states can make.

My intent here is not to lay out a comprehensive set of positions on international law. Rather, as I

have done with respect to domestic law, I will tell you how DoD lawyers address some of the

international law issues that today’s military cyber operations present.

I will start with some basics. It continues to be the view of the United States that existing

international law applies to State conduct in cyberspace. Particularly relevant for military

operations are the Charter of the United Nations, the law of State responsibility, and the law of

war. To determine whether a rule of customary international law has emerged with respect to

certain State activities in cyberspace, we look for sufficient State practice over time, coupled

with opinio juris—evidence or indications that the practice was undertaken out of a sense that it

was legally compelled, not out of a sense of policy prudence or moral obligation.

As I discussed a few minutes ago, our policy leaders assess that the threat environment

demands action today—our clients need our advice today on how international legal rules apply

when resorting to action to defend our national interests from malicious activity in cyberspace,

notwithstanding any lack of agreement among States on how such rules apply. Consequently, in

reviewing particular operations, DoD lawyers provide advice guided by how existing rules apply

to activities in other domains, while considering the unique, and frequently changing, aspects of

cyberspace.

First, let’s discuss the international law applicable to uses of force. Article 2(4) of the

Charter of the United Nations provides that “All Members shall refrain in their international

relations from the threat or use of force against the territorial integrity or political independence

of any state, or in any other manner inconsistent with the Purposes of the United Nations.” At the

same time, international law recognizes that there are exceptions to this rule. For example, in the

684 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

exercise of its inherent right of self-defense a State may use force that is necessary and

proportionate to respond to an actual or imminent armed attack. This is true in the cyber context

just as in any other context.

Depending on the circumstances, a military cyber operation may constitute a use of force

within the meaning of Article 2(4) of the U.N. Charter and customary international law. In

assessing whether a particular cyber operation—conducted by or against the United States—

constitutes a use of force, DoD lawyers consider whether the operation causes physical injury or

damage that would be considered a use of force if caused solely by traditional means like a

missile or a mine. Even if a particular cyber operation does not constitute a use of force, it is

important to keep in mind that the State or States targeted by the operation may disagree, or at

least have a different perception of what the operation entailed.

Second, the international law prohibition on coercively intervening in the core functions

of another State (such as the choice of political, economic, or cultural system) applies to State

conduct in cyberspace. For example, “a cyber operation by a State that interferes with another

country’s ability to hold an election” or that tampers with “another country’s election results

would be a clear violation of the rule of non-intervention.” Other States have indicated that they

would view operations that disrupt the fundamental operation of a legislative body or that would

destabilize their financial system as prohibited interventions.

There is no international consensus among States on the precise scope or reach of the

non-intervention principle, even outside the context of cyber operations. Because States take

different views on this question, DoD lawyers examining any proposed cyber operations must

tread carefully, even if only a few States have taken the position publicly that the proposed

activities would amount to a prohibited intervention.

Some situations compel us to take into consideration whether the States involved have

consented to the proposed operation. Because the principle of non-intervention prohibits “actions

designed to coerce a State … in contravention of its rights,” it does not prohibit actions to which

a State voluntarily consents, provided the conduct remains within the limits of the consent given.

Depending on the circumstances, DoD lawyers may also consider whether an operation

that does not constitute a use of force could be conducted as a countermeasure. In general,

countermeasures are available in response to an internationally wrongful act attributed to a State.

In the traditional view, the use of countermeasures must be preceded by notice to the offending

State, though we note that there are varying State views on whether notice would be necessary in

all cases in the cyber context because of secrecy or urgency. In a particular case it may be

unclear whether a particular malicious cyber activity violates international law. And, in other

circumstances, it may not be apparent that the act is internationally wrongful and attributable to a

State within the timeframe in which the DoD must respond to mitigate the threat. In these

circumstances, which we believe are common, countermeasures would not be available.

For cyber operations that would not constitute a prohibited intervention or use-of-force,

the Department believes there is not sufficiently widespread and consistent State practice

resulting from a sense of legal obligation to conclude that customary international law generally

prohibits such non-consensual cyber operations in another State’s territory. This proposition is

recognized in the Department’s adoption of the “defend forward” strategy: “We will defend

forward to disrupt or halt malicious cyber activity at its source, including activity that falls below

the level of armed conflict.” The Department’s commitment to defend forward including to

counter foreign cyber activity targeting the United States—comports with our obligations under

international law and our commitment to the rules-based international order.

685 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

The DoD OGC view, which we have applied in legal reviews of military cyber operations

to date, shares similarities with the view expressed by the U.K. Government in 2018. We

recognize that there are differences of opinion among States, which suggests that State practice

and opinio juris are presently not settled on this issue. Indeed, many States’ public silence in the

face of countless publicly known cyber intrusions into foreign networks precludes a conclusion

that States have coalesced around a common view that there is an international prohibition

against all such operations (regardless of whatever penalties may be imposed under domestic

law).

Traditional espionage may also be a useful analogue to consider. Many of the techniques

and even the objectives of intelligence and counterintelligence operations are similar to those

used in cyber operations. Of course, most countries, including the United States, have domestic

laws against espionage, but international law, in our view, does not prohibit espionage per se

even when it involves some degree of physical or virtual intrusion into foreign territory. There is

no anti-espionage treaty, and there are many concrete examples of States practicing it, indicating

the absence of a customary international law norm against it. In examining a proposed military

cyber operation, we may therefore consider the extent to which the operation resembles or

amounts to the type of intelligence or counterintelligence activity for which there is no per se

international legal prohibition.

Of course, as with domestic law considerations, establishing that a proposed cyber

operation does not violate the prohibitions on the use of force and coercive intervention does not

end the inquiry. These cyber operations are subject to a number of other legal and normative

considerations.

As a threshold matter, in analyzing proposed cyber operations, DoD lawyers take into

account the principle of State sovereignty. States have sovereignty over the information and

communications technology infrastructure within their territory. The implications of sovereignty

for cyberspace are complex, and we continue to study this issue and how State practice evolves

in this area, even if it does not appear that there exists a rule that all infringements on sovereignty

in cyberspace necessarily involve violations of international law.

It also longstanding DoD policy that U.S. forces will comply with the law of war “during

all armed conflicts however such conflicts are characterized and in all other military operations.”

Even if the law of war does not technically apply because the proposed military cyber operation

would not take place in the context of armed conflict, DoD nonetheless applies law-of-war

principles. This means that the jus in bello principles, such as military necessity, proportionality,

and distinction, continue to guide the planning and execution of military cyber operations, even

outside the context of armed conflict.

DoD lawyers also advise on how a proposed cyber operation may implicate U.S. efforts

to promote certain policy norms for responsible State behavior in cyberspace, such as the norm

relating to activities targeting critical infrastructure. These norms are non-binding and identifying

the best methods for integrating them into tactical-level operations remains a work in progress.

But, they are important political commitments by States that can help to prevent miscalculation

and conflict escalation in cyberspace. DoD OGC, along with other DoD leaders, actively

supports U.S. State Department-led initiatives to build and promote this framework for

responsible State behavior in cyberspace. This includes participation in the UN Group of

Governmental Experts and an Open-Ended Working Group on information and communications

technologies in the context of international peace and security. These diplomatic engagements

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are an important part of the United States’ overall effort to protect U.S. national interests by

promoting stability in cyberspace.

* * * *

On May 22, 2020, Ambassador Cherith Norman Chalet, acting deputy permanent representative to the UN, delivered the U.S. statement at a UN Security Council meeting on cyber stability and responsible state behavior in cyberspace, held via video teleconference. Ambassador Chalet’s remarks are excerpted below and available at https://usun.usmission.gov/remarks-at-a-un-security-council-arria-formula-meeting-on-cyber-stability-and-responsible-state-behavior-in-cyberspace-via-vtc/.

___________________

* * * *

The United States remains committed to working with all member states to safeguard the

extraordinary benefits of cyberspace. We must all redouble our efforts—and not just in New

York and Geneva—to create accountability for state actions in cyberspace. Cyberspace has

become a central and indispensable domain of global activity, and its protection through

responsible state behavior is critical to ensuring the maintenance of international peace and

security.

The United Nations began discussing the issue of international security in cyberspace in

the early 2000s. For years, the international community struggled to develop an appropriate and

functional framework for enhancing international peace and security in this domain. Since given

the nature of the technology, traditional arms control approaches were not entirely practical or

useful references. Nevertheless, through its three consensus reports in 2010, 2013, and 2015, the

UN Group of Governmental Experts succeeded at established a framework of responsible state

behavior to enable international cyber stability.

This framework consists of three parts: one, the applicability of international law to state

behavior in cyberspace; two, voluntary non-binding norms of state behavior applicable in

peacetime; and three, the implementation of practical Confidence Building Measures, or CBMs.

This framework is strong and sustainable because it is not tied to the current state of technology

and, therefore, not prone to becoming obsolete. It is focused on real-world effects of actions

taken by state actors in the cyberspace. Moreover, the General Assembly, by consensus, affirmed

all three GGE reports. Broad international consensus and the General Assembly’s strong and

repeated support around this framework is the signature accomplishment of our collective cyber

diplomacy over the past decade. These successes must be fully protected and observed.

In addition to the contributions of the UN GGE process, regional organizations, including

the OAS, OSCE, and the ASEAN Regional Forum, have also reinforced and enhanced this

framework. Those groups focused on improving regional security have made great strides in

implementing practical confidence building measures in their regions to improve cyber stability.

There’s no doubt that such measures can contribute substantially to conflict prevention and

stability, and we commend these organizations for their contributions to this effort. The United

States, like many others in the international community, share a vision for maintaining peace,

security, and stability in cyberspace. That is why in 2018, the United States reaffirmed its

687 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

commitment to this vision in our National Cyber Strategy, which commits the United States to

preserve and build upon this framework. It is also why working with other nations to help

strengthen their cyber capacity is an integral part of our approach.

Even though certain states appear willing to undermine this framework, universalizing it

is in all member states’ interests. We must work to ensure that states wanting to act responsibly

in cyberspace have the means to do so, which includes protecting their networks from malicious

state and non-state actors. In this regard, the United States pledges its continued support to

likeminded partners in their efforts to enhance cybersecurity and counter malicious cyber actors,

including combating cybercrime and strengthening public institutions’ protection from malicious

cyber actors.

These issues remain a top priority during the COVID-19 pandemic. We have witnessed

malicious cyber activity that appears designed to undermine the United States and our

international partners’ efforts to protect, assist, and inform the public during this global

pandemic. Malicious cyber activity that impairs the ability of hospitals and healthcare systems to

deliver critical services, for instance, could have deadly results. As noted in the framework,

states should refrain in peacetime from cyber activities that intentionally damage critical

infrastructure – including healthcare and public health services and other important public

services. When states do not abide by the framework of responsible state behavior, there will be

consequences.

In closing, let me be clear, the United States will continue to uphold the stability of

cyberspace and the framework, including through the Group of Governmental Experts and the

Open-Ended Working Group.

* * * *

B. CONVENTIONAL WEAPONS

Lethal Autonomous Weapons Systems (“LAWS”) On February 20, 2020, Attorney-Adviser in the State Department’s Office of the Legal Adviser Amanda Wall addressed the Rio Seminar on Autonomous Weapon Systems on the subject of “LAWS and Human-Machine Interaction.” Her remarks are excerpted below and available at http://funag.gov.br/biblioteca/download/laws_digital.pdf.

___________________

* * * *

I am a member of the U.S. delegation to meetings of the High Contracting Parties to the CCW

and the GGE on emerging technologies in the area of Lethal Autonomous Weapons Systems,

and have participated in the last several meetings in that capacity.

I am going to focus my presentation today on the views of the United States on human-

machine interaction in the area of LAWS. This has been a topic that has been discussed at some

length at the GGE, with a wide diversity of views presented, but having observed those debates

personally, my own view is that there is actually a lot more common ground between the

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positions being expressed at the GGE, and the differences are not so vast as they might seem. In

fact, I would posit that the states participating at the GGE actually have a lot more in common

than they realize.

Let me also say, before I begin, that the United States remains fully supportive of the

work of the GGE and hopes to help to accomplish a strong, substantive outcome by the end of its

current two-year mandate in 2021.

In my time today, first, I am going to talk about how the United States understands

human-machine interaction in the area of emerging technologies in LAWS. Second, I am going

to spend a few minutes talking about why we think that the concept of “human control,” as some

have characterized it, does not fully capture the range of considerations that need to be

undertaken when developing policies and programs for responsible development and use of

LAWS, and why we think it actually may be an oversimplification of some of the very

complicated issues at stake. And, finally, I am going to say a few words about what, we would

argue, should be the focus of the GGE in this regard over the next two years. My remarks today

draw heavily from working papers and views that the U.S. delegation has presented to the GGE,

and, in particular, a U.S. working paper on human-machine interaction.

But to begin, I want to make one point as a legal matter. As Ambassador Candeas noted

in his introduction this morning, it is important to acknowledge first and foremost that IHL,

including the fundamental principles and rules of distinction, proportionality, military necessity,

and precautions in attack, continue to apply regardless of what type of weapon is used. This is

reflected in the GGE’s Guiding Principle (a), as well as in the GGE’s conclusion in paragraph

17(a) of the GGE’s 2019 report.2

In addition to helping assess whether a new weapon falls under a legal prohibition or how

IHL requirements apply, the fundamental principles of international humanitarian law may also

serve as a guide in answering novel ethical or policy questions in human-machine interaction that

are presented by these emerging technologies. For example, it may be appropriate to consider the

following:

• Does military necessity justify developing or using this new technology?

• Under the principle of humanity, does the use of this new technology reduce

unnecessary suffering?

• Are there ways that this new technology can enhance the ability to distinguish between

civilians and combatants?

• And, under the principle of proportionality, has sufficient care been taken to avoid

creating unreasonable or excessive incidental effects?

There has been broad consensus at the GGE that IHL is applicable to the use of force,

including the use of force that is reliant on autonomy or autonomous features and functions. But

how do we go about ensuring that the law, in particular IHL, is complied with in the use of these

weapons, and how do we develop good practices for responsible development and use of these

weapons?

Effectuating the intent of commanders and operators

A big part of the answer to this question rests in human-machine interaction, which is

what I have been asked to discuss today. From the U.S. perspective, the key issue for human-

machine interaction in emerging technologies in the area of LAWS is ensuring that machines

effectuate the intent of commanders and operators of the weapons systems. Weapons that do

what commanders and operators intend them to do can give effect to their specific intentions to

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conduct operations in compliance with IHL and to minimize harm to civilians and civilian

objects.

Much of the U.S. policy and practice in this area is laid out in a 2012 Policy Directive

issued by our Department of Defense. It is DoD Directive 3000.09, titled “Autonomy in Weapon

Systems.” …

Let me elaborate upon the concept of good practices for effectuating the intent of

commanders and operators. It is not necessarily about having a human executing or controlling

every step of a weapon’s operation manually: this does not happen with many weapons systems

that have been in operation for decades. Instead, it is about taking practical steps that, among

other things, enable personnel to exercise judgment over the use of force in an armed conflict,

and reduce the risk of unintended combat engagements So, how do we develop and use weapons

in a way that ensures that weapons give effect to human intent? What measures should we take?

Measures to ensure the use of autonomy in weapon systems effectuates human

intentions

First, we need to think about how to minimize the probability and consequences of

failures in weapon systems that could lead to engagements that the commander and operators did

not intend. This could happen either because a weapon engaged a target that was not the intended

target, or because it created unacceptable levels of collateral damage. I would note that even an

attack against previously authorized targets could ultimately be “unintended” if there are

significant changes in circumstances between the time of authorization and when the weapon

engaged targets, such that the authorizing official no longer intended the targets to be engaged.

So there is a temporal aspect to it, as well.

There are a number of ways that guidelines in the development and use of weapon

systems can help minimize the probability and consequences of failures in weapon systems—

failures that could lead to unintended engagements. One example is that an autonomous system

might be programmed to operate only within specific geographic boundaries. If deployed and

limited to an area that was a military objective, like an enemy military headquarters complex,

then its use would be analogous to the use of other weapons, like artillery, that are often used to

target areas of land that qualify as military objectives. Another example might be an autonomous

weapon that is equipped with sensors that are designed to detect specific “signatures”—or

unique, identifying characteristics that would be specific to a military objective, like frequencies

of electromagnetic radiation that are generally not found in nature or among civilian objects.

Many states have already used weapons that detect the specific electromagnetic signals emitted

by enemy radar to help ensure that a target is a military objective. These are all examples of

ways that weapons can be developed and used to help effectuate the intent of a commander or

operator by minimizing the probability of unintended engagements and minimizing the

consequences of such engagements if they occur.

Second, we need to think about how to help ensure that weapon systems function as

anticipated. This includes engineering weapon systems to perform reliably. The DoD Directive

that I mentioned before puts in place requirements for verification and validation, and for testing

and evaluation of hardware and software to make sure that they function as anticipated. For

example, before fielding weapon systems that would use autonomy in novel ways, those reviews

must “assess system performance, capability, reliability, effectiveness, and suitability under

realistic conditions.” The Directive also requires “safeties, anti-tamper mechanisms, and

information assurance” to ensure that the weapon functions as it was anticipated to function,

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namely by helping address and minimize the probability or consequence of failures that could

lead to unintended engagements or to loss of control of the system, by adversaries or others.

Third, we need to think about how to help ensure that personnel properly understand the

weapon systems. This includes training personnel, establishing clear human-machine interfaces,

and developing clear doctrine and procedures for use. Studies of accidents involving human use

of automation have shown that failures can often result from operator error, and that better

training and adherence to established tactics, techniques, and procedures and doctrine could have

prevented those mistakes. That is why the DoD Directive generally requires the establishment of

such “[t]raining, doctrine, and tactics, techniques, and procedures”—what we call TTPs. And,

before systems that employ autonomy in new ways are fielded, senior officials must determine

that “[a]dequate training, TTPs, and doctrine are available, periodically reviewed, and used by

system operators and commanders to understand the functioning, the capabilities, and the

limitations of the system’s autonomy in realistic operational conditions.”

Further to this end, the interface between humans and machines should be clear “[i]n

order for operators to make informed and appropriate decisions in engaging targets.” This is why

the DoD Directive requires the interface between people and machines for autonomous and

semi-autonomous weapon systems to:

(a) Be readily understandable to trained operators;

(b) Provide traceable feedback on system status; and

(c) Provide clear procedures for trained operators to activate and deactivate system

functions.

These are just some examples; there are a number of measures that can be taken to help

ensure that weapon systems that use autonomy are developed and used to effectuate human

intention in the use of force. These measures are outlined in greater detail in the working paper

referenced above, which I have provided to this conference and is also available on the CCW’s

website.

Why not “human control”?

One question you may be asking is, why not call this “human control”? After outlining

the policies that our own Department of Defense has in place with regard to the use of autonomy

in weapon systems, my hope is that people in the audience are thinking, well, that sounds a lot

like the measures that would be useful to ensure meaningful human control—because, as I said at

the outset, I think there is much common ground between the position that we have articulated

and the position that has been articulated by those who say we need a norm of meaningful human

control. But, I think there are some key reasons why the U.S. view is that “meaningful human

control” simply is not an adequate way to describe what is needed for responsible use and

development of LAWS, and we continue to think that the term “human control” risks obscuring

some of the genuine challenges that these technologies present.

First, no one can really agree on what “human control” means. In discussing this issue at

the GGE, there have been almost as many different ways of describing “human control” as there

have been delegations in the room. So it has not proven to be a useful construct for building

consensus among members of the GGE.

Second, it is also not a very useful umbrella term as a practical matter. How a weapon

system is controlled is often very specific to the particularities of that weapon system, and

control systems can vary greatly from system to system. This is part of the reason why past

regulation of weapons systems under IHL has not included broadly applicable standards for

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weapon control—the concept in practice does not work very well across different types of

weapons.

Third, I believe the concept of human control mistakes the “means” for the “ends.”

Existing IHL instruments, such as the CCW and its Protocols, do not seek to enhance “human

control” as such. Instead, they seek to ensure that the use of those weapons is consistent with

IHL. Although control over a weapon system can be a useful way in certain circumstances to

ensure that a weapon system is used in compliance with IHL, it is not the only way or always the

best way to do so; that is, “control” is not, and should not be, a means in and of itself—but rather

one of many ways that states can consider in best effectuating human intent in the use of a

weapon system.

Some may say that it is important to emphasize “human control” because they view

developments in the use of automation or autonomy in weapons system as actually decreasing

human control over the use of force. And I think we would say that this emphasis is not

necessarily correct. Technical sophistication does not necessarily mean that there is any less

human involvement in the decision-making regarding how a weapon is used. In fact, the whole

point of some of this technology, for example, sensors and computers, is that it allows humans to

have more options for when, where, and how force is used; that is, essentially to make judgments

about using force and to have the operator’s intent and judgments effectuated by machines

without the operator being required to control every step of that machine’s process manually.

Automated or software control systems can also reduce the degree to which effectiveness in the

execution of those important decisions depends on the perception and skill of an operator, which

can be negatively impacted in combat by various factors, such as fatigue, fear, or deception. And

the use of “smart” weaponry with autonomous functions has actually, I believe, in many ways

increased the degree of control that states exercise over the use of force. For example, by

increasing the precision of the execution of decision-making, the operator arguably is ensuring

better control over the use of force, even though it is not through manual control of every step of

a weapon’s deployment and use. Theoretically, another way to think about it is that, if an

operator might be able to exercise control over every aspect of a weapon system, but the operator

is only reflexively pushing a button that is recommended to him or her by the system, the human

is not really exercising any judgment, even though the human operator is exercising control in

pushing a particular button. What we are looking for here is human intention and human

judgment, not necessarily control.

On the other hand, judgment can be implemented through the use of automation. For

example, use of algorithms or even autonomous functions that take control away from human

operators can better effectuate human intention and avoid accidents. One system that is a useful

case study is the Automatic Ground Collision Avoidance System, which was developed by the

U.S. Air Force in order to help prevent “controlled flight into terrain” accidents. The system

essentially assumes control of the aircraft when an imminent collision with the ground is

detected and then returns control back to the human pilot once the collision is averted. This can

help avoid accidents through an automatic feature that actually removes control by the human

operator briefly in certain circumstances. Another example would be certain defensive

autonomous weapon systems, such as the AEGIS Weapon System and Patriot Air and Missile

Defense System, which have autonomous functions that assist in targeting incoming

missiles. The machine can strike incoming projectiles with much greater speed or accuracy than

a human gunner could achieve manually—so, although the human may not manually control the

speed at which the machine is operating, the human is still exercising judgment over the use of

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force. The machine is really just effectuating that intention and that judgment more efficiently

than a human could do so himself or herself.

Finally, some might argue that it is important to emphasize control because of concerns

that the use of autonomous weapons systems somehow removes individuals from responsibility

for decisions to use force, which are some of the gravest and most serious decisions that a human

being can make. But we do not believe this is true. Human actors are responsible for their

decisions to use force regardless of the nature of weapon used. The lack of manual control over a

weapon system does not remove this responsibility or create an accountability gap. This is, in

fact, recognized in the GGE’s second Guiding Principle. Machines may be able to synthesize

data and apply algorithms faster than a person could, and they may be able to do so more

accurately. But machines are not moral agents, and human beings do not escape responsibility

for their decisions by using a weapon with autonomous functions to execute those decisions, in

the same way that human beings do not escape responsibility for taking a life with a knife or a

gun rather than with their bare human hands.

So, there is no need to stigmatize autonomy as either preventing humans from being held

accountable for their decisions, or as inherently reducing control: autonomy does not necessarily

do either one.

What next for human-machine interaction?

So, with all of this said, what should come next with regard to human-machine

interaction? The reality is that technology

is developing rapidly, and standards developed based on our understandings today could be

obsolete by tomorrow. So, we need to focus on how to ensure that weapons incorporating those

technologies are used in compliance with IHL, and used responsibly, tomorrow. How can we do

that?

The U.S. view is that states should take a proactive approach in addressing human-

machine interaction. States seeking to develop new uses for autonomy in weapon systems should

be affirmatively trying to identify and address these issues in their respective processes for

managing the life-cycle of the weapons. One way to do this is to emphasize the importance of

weapons review policies and practices—if states are thoroughly and properly conducting reviews

of their systems during development and prior to use, they can assess whether the specifics of

that system can be used consistently with IHL rules and principles, and can be used in a

responsible manner.

For example, the DoD Directive requires senior officials to review weapon systems that

use autonomy in new ways. This review, which is additional to the normal weapons review

processes, is required before a system enters formal development and, again, before fielding, to

ensure that military, acquisition, legal, and policy expertise is brought to bear as these new types

of weapons are being developed. You have heard me mention reviews several times during the

course of my remarks today, but I will say it once more: robust review policies and procedures to

ensure lawful and responsible use are one of the most effective ways we can think of to ensure

that weapons that are developed tomorrow, and next week, and next year, are used lawfully and

responsibly.

Another way to do this is by working to clarify how existing IHL applies to particular

systems—the United States developed a paper for the GGE in March 2019 that worked through

three general scenarios for the use of autonomous functions in weapon systems and how IHL

would apply to those three scenarios. More work could be done on this if states are willing to

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share their intended use scenarios and their interpretations of how IHL would apply in such

cases.

But in our view, there is no better place to do this than in the GGE—and the United

States continues to see real value in the conversations that are happening at the GGE, talking

through these very difficult issues in a forum that includes technological, military, and legal

experts from governments, as well as participation by those from outside of governments. The

GGE is really a remarkable and unique venue: a standing body with a mandate to discuss this

extremely complicated, politically fraught topic in a non-politicized way that is grounded in IHL.

Where else do we have a body so well-suited to be working through these difficult issues? And,

in that light, the United States looks forward in particular to continuing these conversations over

the course of the next two years. And we look forward to contributing to a strong outcome before

the end of the current two-year mandate of the GGE. Thank you.

* * * *

On September 11, 2020, the United States provided a statement at the group of government experts (“GGE”) in Geneva on “further consideration of the human element in the use of lethal force and aspects of human-machine interaction in the development, deployment and use of emerging technologies in the area of LAWS.” The statement is excerpted below and available at https://geneva.usmission.gov/2020/09/30/group-of-governmental-experts-on-lethal-autonomous-weapons-systems-laws-agenda-item-5c/.

___________________

* * * *

The United States recognizes the keen interest many GGE participants have expressed in

discussing further the human element and aspects of human-machine interaction in the

development and use of emerging technologies in the area of LAWS. We agree that these are

topics upon which further common understandings can and should be built, given the range of

views currently expressed by various States. We believe that Guiding Principle (c) is an excellent

basis on which we can build these additional common understandings. This guiding principle

recognizes that human-machine interaction should ensure IHL compliance, and also recognizes

the need to consider human-machine interaction comprehensively, across the life cycle of the

weapon system. Therefore, in our view, a positive next step for the GGE in this area would be to

elaborate on good practices in human-machine interaction that can strengthen compliance with

IHL.

In our commentary on Guiding Principle (c), the United States proposed a new

conclusion on human-machine interaction for the GGE’s consideration, along these lines. It

begins by stating that:

“Weapons systems based on emerging technologies in the area of LAWS should

effectuate the intent of commanders and operators to comply with IHL, in particular, by avoiding

unintended engagements and minimizing harm to civilians and civilian objects.”

This conclusion is drawn from real-world practice in human-machine interaction and also

recognizes that IHL imposes requirements on human beings. Therefore, good practices in

human-machine interaction to strengthen compliance with IHL should effectuate human beings’

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intent to comply with IHL. Our commentary then goes on to elaborate three categories of

measures to effectuate this objective:

a. Weapons systems based on emerging technologies in the area of LAWS should be

engineered to perform as anticipated. This should include verification and validation and testing

and evaluation before fielding systems.

b. Relevant personnel should properly understand weapons systems based on emerging

technologies in the area of LAWS. Training, doctrine, and tactics, techniques, and procedures

should be established for the weapon system. Operators should be certified by relevant

authorities that they have been trained to operate the weapon system in accordance with

applicable rules. And,

c. User interfaces for weapons systems based on emerging technologies in the area of

LAWS should be clear in order for operators to make informed and appropriate decisions in

engaging targets. In particular, interface between people and machines for autonomous and semi-

autonomous weapon systems should: (i) be readily understandable to trained operators;

(ii) provide traceable feedback on system status; and (iii) provide clear procedures for trained

operators to activate and deactivate system functions.

We are interested in the views of GGE participants on these proposed new conclusions,

which reflect good practices that can strengthen compliance with IHL. These proposed new

conclusions provide the basis for more detailed discussion regarding good practices in

engineering weapons systems, training personnel, and human-machine interfaces. We hope the

GGE can productively articulate good practices that can strengthen compliance with IHL as a

means of developing consensus recommendations on the issue of human-machine interaction.

Human responsibility is a critical dimension of the human element in the use of lethal

force.

We also believe it would be productive for the GGE to address how well-established

international legal principles of State and individual responsibility apply to States and persons

who use weapon systems with autonomous functions. In its commentary on Guiding Principle

(b), the United States has proposed eight new conclusions along these lines for the GGE’s

consideration.

1. Under principles of State responsibility, every internationally wrongful act of a State,

including such acts involving the use of emerging technologies in the area of LAWS, entails the

international responsibility of that State.

2. A State remains responsible for all acts committed by persons forming part of its

armed forces, including any such use of emerging technologies in the area of LAWS, in

accordance with applicable international law.

3. An individual, including a designer, developer, an official authorizing acquisition or

deployment, a commander, or a system operator, is responsible for his or her decisions governed

by IHL with regard to emerging technologies in the area of LAWS.

4. Under applicable international and domestic law, an individual remains responsible for

his or her conduct in violation of IHL, including any such violations involving emerging

technologies in the area of LAWS. The use of machines, including emerging technologies in the

area of LAWS, does not provide a basis for excluding legal responsibility.

5. The responsibilities of any particular individual in implementing a State or a party to a

conflict’s obligations under IHL may depend on that person’s role in the organization or military

operations, including whether that individual has the authority to make the decisions and

judgments necessary to the performance of that duty under IHL.

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6. Under IHL, a decision, including decisions involving emerging technologies in the

area of LAWS, must be judged based on the information available to the decision-maker at the

time and not on the basis of information that subsequently becomes available.

7. Unintended harm to civilians and other persons protected by IHL from accidents or

equipment malfunctions, including those involving emerging technologies in the area of LAWS,

is not a violation of IHL as such. And,

8. States and parties to a conflict have affirmative obligations with respect to the

protection of civilians and other classes of persons under IHL, which continue to apply when

emerging technologies in the area of LAWS are used. These obligations are to be assessed in

light of the general practice of States, including common standards of the military profession in

conducting operations.

We look forward to discussing these and other proposals with other delegations.

* * * *

On September 19, 2020, the United States provided a statement at the GGE on “possible options for addressing the humanitarian and international security challenges posed by emerging technologies in the area of LAWS.” The statement is available at https://geneva.usmission.gov/2020/09/30/group-of-governmental-experts-on-lethal-autonomous-weapons-systems-laws-agenda-item-5e/ and excerpted below.

___________________

* * * *

At the outset, the United States wishes to recognize that one of the principal humanitarian and

international security challenges posed by emerging technologies in the area of LAWS, is how to

use these emerging technologies to achieve humanitarian and security benefits. For example,

guiding principle (h) recognizes that emerging technologies in the area of LAWS can be used to

uphold compliance with IHL. Technology can present risks and opportunities, and taking

advantages of those opportunities can be as important as minimizing risks.

One theme that we have emphasized, and that Ambassador Karklins also mentioned

during his presentation, for the GGE to consider is that form must follow function. It would be

counterproductive to determine what form the outcome our work should take before we work

through the substantive issues. We have proposed in our national commentaries and in our

remarks on the other agenda items substantive conclusions for the GGE to consider. While we

continue to support the Chair’s proposal for substantive intercessional work, we fully understand

the need for this work to be as inclusive as possible and are ready to engage on the substance of

these issues with the appropriate modalities.

That said, in the discussions so far, we have not been persuaded that a new treaty is

necessary because we believe existing IHL provides a robust and coherent framework for the

regulation of emerging technologies in the area of LAWS. In addition, we must be cautious

about predicting the course of technological developments, which are rapid and ongoing. It

makes sense to explore formats that allowed for continued discussion, refinement, and iteration.

We would not want to codify conclusions that would be rendered obsolete in light of

technological developments.

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The GGE has done significant work in elaborating guiding principles, and we continue to

believe that the Guiding Principles have offered parties to the CCW the best vehicle for

clarifying and further developing the normative framework that is immediately available to

parties as they navigate emerging technologies in the area of LAWS. We disagree that these

principles’ utility is limited to guiding the work of the GGE—the decision to endorse the

Guiding Principles at last year’s meeting of High Contracting Parties was intended to begin a

broader process of providing parties to the CCW with meaningful outcomes. But we are glad that

there continues to be consensus that the Guiding Principles serve as the foundation for the

GGE’s work. We should continue the very successful approach that we took last year of

considering how we can elaborate on the guiding principles. To that end, we have proposed

further work on guiding principle (a) by clarifying IHL requirements and by articulating how

principles of State and individual responsibility apply. But we also think the GGE should be

compiling and elaborating upon good practices under other Guiding Principles.

For example, Guiding Principle (d) recognizes that State and individual responsibility

must be ensured through the effective implementation of accountability measures, including the

military chain of command. In its commentary on Guiding Principle (d), the United States has

proposed a number of general practices to help ensure accountability in military operations,

including operations involving the use of emerging technologies in the area of LAWS. These

include:

a. Conducting operations under a clear operational chain of command; and

b. Subjecting members of the armed forces to a system of military law and discipline.

The United States has also proposed practices with respect to the use of weapons

systems, including those based on emerging technologies in the areas of LAWs, which can

promote accountability. These are:

a. Rigorous testing of and training on the weapon system, so commanders and operators

understand the likely effects of employing the weapon system.

b. Establishing procedures and doctrine applicable to the use of the weapon system,

which provide standards for commanders and operators on responsible use and under which they

can be held accountable under the State’s domestic law.

c. Using the weapon system in accordance with training, doctrine, and procedures and

refraining from unauthorized uses or modifications of the weapons system.

Additionally, Guiding Principle (e) reaffirms the importance of a robust practice of

conducting reviews of the legality of weapons. Such reviews are a good practice to facilitate the

implementation of international law applicable to weapons and their use in armed conflict, and

can also help ensure that their humanitarian and security benefits are realized, and any risks

mitigated. To that end, the United States has proposed in its commentary on Guiding Principle

(e) a number of good practices for the legal review of weapons systems.

I highlight a few in particular to this discussion:

1. Legal advisers should be consulted regularly in the development or acquisition process

so that legal issues can be identified and more in-depth reviews can be conducted where

necessary. A weapon system under modification should be reviewed to determine whether the

modification poses any legal issues. New concepts for the employment of existing weapons

should also be reviewed, when such concepts differ significantly from the intended uses that

were considered when those systems were previously reviewed.

* * * *

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5. The legal review should advise those developing or acquiring the weapon system or its

concepts of employment to consider potential measures to reduce the likelihood that use of the

weapon will cause harm to civilians or civilian objects. And,

6. Persons conducting the legal review should understand the likely effects of employing

the weapon in different operational contexts. Such understandings should be produced through

realistic system developmental and operational test and evaluation.

Bearing in mind national security considerations or commercial restrictions on

proprietary information, we also believe the GGE should recommend that States share good

practices on weapons reviews or legal reviews of particular weapons where appropriate.

Finally, both Guiding Principle (f) and Guiding Principle (g) provide an excellent starting

point for addressing humanitarian and security challenges that may arise. Risk assessments, in

particular, allow for a weighing of the benefits of the emerging technologies against potential

risks and also allow for adjustments to be made as further research and development occurs. Risk

assessments can also support the training of commanders and operators by helping them

understand the function, capabilities, limitations, and likely effects of using a weapon system.

The GGE should consider building on the work reflected in paragraphs 23(a) and 23(b) of its

2019 report by further cataloging potential risks and mitigation measures that should be

considered in the design, development, testing, and deployment of weapons systems based on

emerging technologies in the area of LAWS.

* * * * On September 21, 2020, the United States provided a statement on the potential

challenges to international humanitarian law (“IHL”) posed by emerging technologies in the area of LAWS. The statement is excerpted below and available at https://geneva.usmission.gov/2020/09/30/group-of-governmental-experts-on-lethal-autonomous-weapons-systems-laws-agenda-item-5a/.

* * * *

Thank you, Mr. Chair. The United States appreciates the focus of this agenda item on the

application of IHL to emerging technologies in the area of lethal autonomous weapons systems

(LAWS). Guiding Principle (a) reflects the foundational premise that IHL applies to these

weapons, and the GGE’s 2019 report contains significant conclusions on IHL. Of course, much

more work can be done on IHL. This work on understanding how IHL applies is critical to

effectively implementing the other guiding principles, including guiding principles (b), (c), (d),

(e), and (h).

Indeed, reaching common understanding on what existing IHL requires could also help

us re-solve diverging perspectives on whether new law or norms are needed, as such an effort

would help us to better understand our respective legal positions and determine whether these

diverging perspectives are based on different understandings of the requirements imposed by

existing law.

Mr. Chair, the GGE should build on its successful work on IHL by further clarifying IHL

re-quirements applicable to the use of emerging technologies in the area of LAWS. In our

national commentary to Guiding Principle (a), we have proposed that this be done by considering

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how militaries have generally used autonomous functions in weapon systems and articulating

conclu-sions about these general use scenarios.

In particular, we propose examining how the following uses of emerging technologies in

the area of LAWS can be consistent with IHL:

1. Using autonomous functions to effectuate more accurately and reliably a commander

or operator’s intent to strike a specific target or target group;

2. Using emerging technologies in the area of LAWS to inform decision-making.

3. Using weapons systems that autonomously select and engage targets where the human

operator has not expressly intended to strike a specific target or group of targets when ac-tivating

the weapon system.

These use scenarios frame a number of questions that are worth further exploration, such

as: when is it consistent with IHL for a decision-maker to rely on a machine assessment to

consider a target to be a military objective? What factors should inform a proportionality

assessment re-garding the employment of weapons systems that autonomously

select and engage targets?

We have proposed conclusions on these and other issues. For example, we propose that

the GGE build on last year’s report, which recognized the importance of precautions, by

elaborating on the

types of precautions that States have employed in weapon systems with autonomous

functions. On page 4 of our national commentary, we proposed the following:

Feasible precautions must be taken in use of weapon systems that autonomously select

and engage targets to reduce the expected harm to civilians and civilian ob-jects. Such

precautions may include:

i. Warnings (e.g., to potential civilian air traffic or notices to mari-ners);

ii. Monitoring the operation of the weapon system; and

iii. Activation or employment of self-destruct, self-deactivation, or self-neutralization

mechanisms (e.g., use of rounds that self-destruct in flight or torpedoes that sink to the bottom if

they miss their targets).

Reaching more granular understandings like this of IHL requirements would strengthen

the nor-mative and operational framework. For example, it would improve our ability to conduct

legal review of weapons, to train personnel to comply with IHL requirements, and to apply

principles of State and individual responsibility.

We plan to discuss the issue of human-machine interaction in greater detail during the

appropriate agenda item later this week, but let me just note that in our view, IHL does not

establish a requirement for “human control” as such. Rather, IHL seeks, inter alia, to ensure the

use of weapons is consistent with the fundamental principles and requirements of distinction,

proportionality, and precautions.

The application of IHL to emerging technologies in the area of LAWS is a critical topic,

and we welcome today’s discussion and continued discussions with other delegations regarding

the more technical legal conclusions that we’ve proposed in working papers and our national

commentary regarding how IHL applies in these three use scenarios. In particular, we would

welcome more focused discussions with legal experts on these issues as part of our ongoing

work.

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On September 22, 2020, the United States provided a statement at the GGE on, “characterization of the systems under consideration in order to promote a common understanding on concepts and characteristics relevant to the objectives and purposes of the Convention.” The statement is excerpted below and available at https://geneva.usmission.gov/2020/09/30/group-of-governmental-experts-on-lethal-autonomous-weapons-systems-laws-agenda-item-5b/

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The United States continues to support identifying general characteristics of systems that are

under the GGE’s consideration in order to facilitate the GGE’s understanding of the relevant

concepts and issues. The flexibility inherent in this approach of identifying characteristics is

important given that scientists and engineers continue to develop new technological

advancements and that our understanding continues to improve. This discussion could also help

delegations understand better what we mean by the terms we are using. Some delegations may be

using the same term to mean different things or some delegations may be using different terms to

mean the same thing.

In identifying characteristics of LAWS, we must not prejudice future decisions regarding

potential outcomes. For example, characteristics should be identified in order to promote

common understandings, not with a view towards advancing a particular policy objective, like a

ban. Similarly, we must be cautious not to make hasty judgments about the value or likely effects

of emerging or future technologies. Frequently, we may change our views of technologies over

time as we gain more experience with them.

In discussing the general characteristics of such systems, we must not lose sight of the

fact that no matter their level of sophistication or how many autonomous features or functions

they have, these weapons systems are tools for human use. Guiding Principle (i) reminds us of

this, stating: “In crafting potential policy measures, emerging technologies in the area of lethal

autonomous weapons systems should not be anthropomorphized.”

In particular, anthropomorphizing emerging technologies in the area of LAWS can lead

to legal and technical misunderstandings that could be detrimental to the efficacy of potential

policy measures. From a technical perspective, anthropomorphizing emerging technologies in the

area of LAWS can lead to mis-estimating machine capabilities. From a legal perspective,

anthropomorphizing emerging technologies in the area of LAWS can obscure the important point

that IHL imposes obligations on States, parties to a conflict, and individuals, rather than

machines. “Smart” weapons cannot violate IHL any more than “dumb” weapons can. Similarly,

machines are not intervening moral agents, and human beings do not escape responsibility for

their decisions by using a weapon with autonomous functions. Anthropomorphizing emerging

technologies in the area of LAWS could incorrectly suggest a diminished responsibility of

human beings simply by the use of emerging technologies in the area of LAWS.

The U.S. Department of Defense policy directive on the use of autonomy in weapon

systems establishes definitions of an “autonomous weapon system” and “semi-autonomous

weapon system” for the purposes of that policy directive. These definitions focus on what we

believe to be the most important issues posed by the use of autonomy in weapon systems — i.e.,

people who employ these weapons can rely on the weapon systems to select and engage targets.

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We will not repeat the specific definitions today, but, for reference, those definitions are

reproduced in the U.S. working paper from November 2017.

In discussing concerns about autonomous weapons, it may be important consider whether

these concerns are fundamentally about the type of weapon system or whether the concerns are

about how weapons systems are used. For example, consider a missile with automated target

recognition capabilities that can select and engage enemy tanks. In one scenario, an operator

identifies a specific target and fires the missile at this target. Under the definitions applied by the

U.S. military, this is a semi-autonomous weapon system. That same weapon system and

capability could, however, be classified as an autonomous system if it is used in a different way.

If the operator does not identify a specific tank, but instead fires the weapon to loiter in an area

and autonomously select and engage tanks, the weapon is classified as an autonomous weapon in

U.S. military practice. The weapon system’s technical characteristics are the same, but how it is

to be used changes whether it is classified as autonomous or semi-autonomous.

Some delegations this morning and yesterday have raised concerns about LAWS being

inherently unpredictable and in the spirit of the interactive discussion that our Chair has invited, I

would ask them to consider whether this concern is based on a characteristic of the weapon

system or whether it is actually based on assumptions about how those weapon systems would be

used. We believe that making progress in our discussions involves developing our common

understanding of how emerging technologies in the area of LAWS can be used consistent with

IHL, and the conclusions we have proposed in our national commentary on guiding principle (a)

try to do that.

* * * *

C. DETAINEES

Al Qahtani v. Trump Mohammed al Qahtani, a Guantanamo detainee, filed a motion in his habeas case asking the court to order the government to conduct a mixed medical commission (“MMC”) to determine his entitlement to repatriation due to his medical issues. Al Qahtani contended that he was eligible for an MMC under Army Regulation AR 190-8, which implements certain international legal obligations applicable in international armed conflicts. The district court ruled in al Qahtani's favor, finding that he is covered by AR 190-8 and ordering the Department of Defense to establish an MMC to evaluate him. Al-Qahtani v. Trump, 443 F.Supp.3d. 116 (D.D.C. 2020). The U.S. government appealed to the D.C. Circuit. The government also moved for a stay pending appeal. The D.C. Circuit granted al Qahtani’s motion to dismiss the appeal on September 29, 2020. Excerpts from the U.S. government’s opposition to al Qahtani’s motion to dismiss are below.* The brief is available at https://www.state.gov/digest-of-united-states-practice-in-international-law/.

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* Editor’s note: On January 11, 2021, the Secretary of the Army issued an “Exception Memorandum,” providing that

AR 190-8 does not apply to any of the detainees presently at the Guantanamo Bay detention facility.

701 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

* * * *

1. a. The Third Geneva Convention establishes rules for the treatment of prisoners of war. The

full protections of the Convention apply to international armed conflicts—that is, to “all cases of

declared war or of any other armed conflict which may arise between two or more of the High

Contracting Parties.” Third Geneva Convention, art. 2. In such conflicts, the Convention applies

even if “one of the Powers in conflict may not be a party to the Convention.” Id. “[T]he Powers

who are parties [to the Convention]” shall “be bound by the Convention in relation to the said

[non-party] Power, if the latter accepts and applies the provisions thereof.” Id. (emphasis added).

By contrast, the full protections of the Convention do not apply to non-international

armed conflicts. “In the case of armed conflict not of an international character,” parties are only

“bound to apply, at a minimum,” certain provisions enumerated in Article 3 of the Convention

that relate to the humane treatment of detainees. Id., art. 3; see generally Hamdan v. Rumsfeld,

548 U.S. 557, 629-31 (2006).

The United States’s conflict with al-Qaida is a non-international armed conflict. Al-Qaida

is a terrorist organization, not a State that is a High Contracting Party to the Third Geneva

Convention. Furthermore, “[n]on-state actors such as al-Qaida” are not “‘Power[s]’ that would

be eligible under Article 2 . . . to secure protection by complying with the Convention’s

requirements.” Hamdan v. Rumsfeld, 415 F.3d 33, 44 (D.C. Cir. 2005) (Williams, J., concurring),

cited approvingly by Hamdan, 548 U.S. at 630. And in any event, al-Qaida neither accepts nor

applies the Convention’s provisions. The full protections of the Convention thus do not apply to

enemy combatants who are part of al-Qaida, as al-Qaida’s members are not entitled to prisoner-

of-war status under the Convention. See White House Press Secretary Announcement of

President Bush’s Determination Re Legal Status of Taliban and Al Qaeda Detainees (Feb. 7,

2002), https://2009-2017.state.gov/s/l/38727.htm. The Convention only obliges the United States

to apply the provisions of Article 3.

b. The Third Geneva Convention requires the parties to an international armed conflict to

repatriate “seriously wounded and seriously sick prisoners of war.” Third Geneva Convention,

art. 109. The Convention’s repatriation provisions are not enumerated in Article 3.

To implement the Convention’s medical-repatriation provisions, the Convention calls for

the appointment of mixed medical commissions to “examine sick and wounded prisoners of war,

and to make all appropriate decisions regarding them.” Id. art. 112. The “appointment, duties,

and functions of these Commissions” are set forth in Annex II to the Convention. Id.

Annex II requires each mixed medical commission to have three members. Third Geneva

Convention annex II, art. 1. One member must be appointed by the detaining power. Id. The two

others “shall belong to a neutral country,” id.; “shall be appointed by the International

Committee of the Red Cross, id. annex II, art. 2; and “shall be approved by the Parties to the

conflict,” id. annex II, art. 3. If the International Committee of the Red Cross cannot arrange for

the appointment of neutral members, such appointment “shall be done by the Power protecting

the interests of the prisoners of war to be examined.” Id. annex II, art. 5. The commission’s

decisions “shall be made by a majority vote,” id. annex II, art. 10, and must be executed by the

detaining power “within three months of the time when it receives due notification of such

decisions,” id. annex II, art. 12.

c. The United States is a High Contracting Party to the Third Geneva Convention. To

carry out the government’s treaty obligations, the Secretaries of the Army, Navy, and Air Force

issued Army Regulation 190-8. This regulation “implements international law” relating to enemy

702 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

prisoners of war and other categories of individuals detained by the U.S. armed forces. AR 190-8

§ 1-1(b); see id. § 1-1(b)(4) (“In the event of conflicts or discrepancies between this regulation

and the Geneva Conventions, the provisions of the Geneva Conventions take precedence.”).

Section 3-12 of the regulation provides for the establishment of mixed medical commissions “to

determine cases eligible for repatriation.” Id. § 3-12(a)(2). The procedures governing those

commissions are based on those specified by Annex II of the Convention. Id.

Section 3-12 states that, to be eligible for examination and potential repatriation, an

individual must fall into one of two categories: Enemy Prisoners of War or Retained Personnel.

AR 190-8 § 3-12(h). The glossary to AR 190-8 defines “Enemy Prisoners of War” as “detained

person[s] as defined in Articles 4 and 5 of the [Third] Geneva Convention,” and in particular, as

individuals “who, while engaged in combat under orders of [their] government, [are] captured by

the armed forces of the enemy.” Id., glossary, sec. II. The glossary defines “Retained Personnel”

as “medical personnel” meeting certain requirements; “[c]haplains”; and “[s]taff of National Red

Cross societies and other voluntary aid societies duly recognized and authorized by their

governments.” Id.; see id. § 3-15(b).

The glossary also addresses “Other Detainee[s].” AR 190-8, glossary, sec. II. “Other

Detainees” are “[p]ersons in the custody of the U.S. Armed Forces who have not been classified

as . . . [Enemy Prisoners of War] (article 4, [GC III]), [Retained Personnel] (article 33, [GC III],

or [Civilian Internees] (article 78, [Fourth Geneva Convention]).” Id.1 Other Detainees “shall be

treated as [Enemy Prisoners of War] until a legal status is ascertained by competent authority.”

Id.20

2. Petitioner Mohammed al Qahtani is a Saudi Arabian national detained at Guantanamo

Bay. In 2005, petitioner filed a habeas petition alleging that his detention was unlawful. The

government responded with a factual return explaining that petitioner—a member of al-Qaida

who unsuccessfully attempted to enter the United States to participate in the September 11

attacks—is being detained pursuant to the 2001 Authorization for Use of Military Force as

informed by the laws of war. Petitioner has not yet filed a traverse challenging the factual basis

for his detention. Petitioner’s habeas case has been stayed at his request since 2010.

* * * *

20 A civilian internee is a “civilian who is interned during armed conflict or occupation for security reasons or for

protection or because he has committed an offense against the detaining power.” AR 190-8, glossary, sec. II. The

regulation does not provide for the examination of civilian internees by a mixed medical commission. Id. § 3-12(h).

703 DIGEST OF UNITED STATES PRACTICE IN INTERNATIONAL LAW

Cross References International crime issues relating to cyberspace, Ch. 3.B.6 CSW resolution on Women and Children Hostages in Armed Conflicts, Chapter 6.B.2.b Children in Armed Conflict, Chapter 6.C Cyber activity sanctions, Ch. 16.A.8 & 16.A.11 Afghanistan, Ch. 17.B.2 U.S. export policy for unmanned aerial systems (“UAS”), Ch. 19.C.2