waltz - origins of war

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The Origins of War in Neorealist TheoryAuthor(s): Kenneth N. WaltzSource: Journal of Interdisciplinary History, Vol. 18, No. 4, The Origin and Prevention ofMajor Wars (Spring, 1988), pp. 615-628Published by: The MIT PressStable URL: http://www.jstor.org/stable/204817Accessed: 17/09/2008 09:23

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Journal of Interdisciplinary History, xvIII:4 (Spring 1988), 615-628.

Kenneth N. WaltzThe Origins of War in Neorealist Theory Likemost historians, many students of international politics have beenskeptical about the possibility of creating a theory that might helpone to understand and explain the international events that interestus. Thus Morgenthau, foremost among traditional realists, wasfond of repeating Blaise Pascal's remark that "the history of theworld would have been different had Cleopatra's nose been a bitshorter" and then asking "How do you systemize that?"1 Hisappreciation of the role of the accidental and the occurrence ofthe unexpected in politics dampened his theoretical ambition.The response of neorealists is that, although difficultiesabound, some of the obstacles that seem most daunting lie inmisapprehensions about theory. Theory obviously cannot explainthe accidental or account for unexpected events; it deals in regu-larities and repetitions and is possible only if these can be identi-fied. A further difficulty is found in the failure of realists toconceive of international politics as a distinct domain about whichtheories can be fashioned. Morgenthau, for example, insisted on"the autonomy of politics," but he failed to apply the concept tointernational politics. A theory is a depiction of the organizationof a domain and of the connections among its parts. A theoryindicates that some factors are more important than others andspecifies relations among them. In reality, everything is related toeverything else, and one domain cannot be separated from others.But theory isolates one realm from all others in order to deal withit intellectually. By defining the structure of international politicalKenneth N. Waltz is Ford Professor of Political Science at the University of California,Berkeley. He is the author of The SpreadofNuclearWeaponsLondon, 1981). He is currentlythe President of the American Political Science Association.The author thanks David Schleicher, who was most helpful in the completion of thisarticle.? I988 by The Massachusetts Institute of Technology and the editors of TheJournal ofInterdisciplinary istory.I Hans J. Morgenthau, "International Relations: Quantitative and Qualitative Ap-proaches," in Norman D. Palmer (ed.), A Design or InternationalRelationsResearch:Scope,Theory,Methods,and Relevance Philadelphia, 1970), 78.


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616 KENNETH N. WALTZsystems, neorealism establishes the autonomy of international pol-itics and thus makes a theory about it possible.2

In developing a theory of international politics, neorealismretains the main tenets of realpolitik, but means and ends areviewed differently, as are causes and effects. Morgenthau, forexample, thought of the "rational" statesman as ever striving toaccumulate more and more power. He viewed power as an endin itself. Although he acknowledged that nations at times act outof considerations other than power, Morgenthau insisted that,when they do so, their actions are not "of a political nature."3 Incontrast, neorealism sees power as a possibly useful means, withstates running risks if they have either too little or too much ofit. Excessive weakness may invite an attack that greater strengthwould have dissuaded an adversary from launching. Excessivestrength may prompt other states to increase their arms and pooltheir efforts against the dominant state. Because power is a pos-sibly useful means, sensible statesmen try to have an appropriateamount of it. In crucial situations, however, the ultimate concernof states is not for power but for security. This revision is animportant one.An even more important revision is found in a shift of causalrelations. The infinite materials of any realm can be organized inendlessly different ways. Realism thinks of causes as moving inonly one direction, from the interactions of individuals and statesto the outcomes that their acts and interactions produce. Mor-genthau recognized that, when there is competition for scarcegoods and no one to serve as arbiter, a struggle for power willensue among the competitors and that consequently the strugglefor power can be explained without reference to the evil born inmen. The struggle for power arises simply because men wantthings, not because of the evil in their desires. He labeled man'sdesire for scarce goods as one of the two roots of conflict, but,even while discussing it, he seemed to pull toward the "other root2 Morgenthau, PoliticsamongNations (New York, 1973; 5th ed.), I . Ludwig Boltzman(trans. Rudolf Weingartner), "Theories as Representations," excerpted in Arthur Dantoand Sidney Morgenbesser (eds.), Philosophy of Science (Cleveland, 1960), 245-252. Neo-realism is sometimes dubbed structural realism. I use the terms interchangeably and,throughout this article, refer to my own formulation of neorealist theory. See Waltz,Theory of InternationalPolitics (Reading, Mass., I979); Robert Keohane (ed.), Neorealismand its Critics(New York, I986).3 Morgenthau, PoliticsamongNations, 27.


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WAR IN NEOREALIST THEORY 617of conflict and concomitant evil"-"the animus dominandi, the de-sire for power." He often considered that man's drive for poweris more basic than the chance conditions under which strugglesfor power occur. This attitude is seen in his statement that "in aworld where power counts, no nation pursuing a rational policyhas a choice between renouncing and wanting power; and, if itcould, the lust for power for the individual's sake would stillconfront us with its less spectacular yet no less pressing moraldefects. "4

Students of international politics have typically inferred out-comes from salient attributes of the actors producing them. ThusMarxists, like liberals, have linked the outbreak of war or theprevalence of peace to the internal qualities of states. Govern-mental forms, economic systems, social institutions, politicalideologies-these are but a few examples of where the causes ofwar have been found. Yet, although causes are specifically as-signed, we know that states with widely divergent economicinstitutions, social customs, and political ideologies have allfought wars. More striking still, many different sorts of organi-zations fight wars, whether those organizations be tribes, pettyprincipalities, empires, nations, or street gangs. If an identifiedcondition seems to have caused a given war, one must wonderwhy wars occur repeatedly even though their causes vary. Vari-ations in the characteristics of the states are not linked directly tothe outcomes that their behaviors produce, nor are variations intheir patterns of interaction. Many historians, for example, haveclaimed that World War I was caused by the interaction of twoopposed and closely balanced coalitions. But then many haveclaimed that World War II was caused by the failure of some statesto combine forces in an effort to right an imbalance of powercreated by an existing alliance.Neorealism contends that international politics can be under-stood only if the effects of structure are added to the unit-levelexplanations of traditional realism. By emphasizing how struc-tures affect actions and outcomes, neorealism rejects the assump-tion that man's innate lust for power constitutes a sufficient causeof war in the absence of any other. It reconceives the causal linkbetween interacting units and international outcomes. According4 Idem, Scientific Man vs. Power Politics (Chicago, I946), 192, 200. Italics added.


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6I8 KENNETH N. WALTZto the logic of international politics, one must believe that somecauses of international outcomes are the result of interactions atthe unit level, and, since variations in presumed causes do notcorrespond very closely to variations in observed outcomes, onemust also assume that others are located at the structural level.Causes at the level of units interact with those at the level ofstructure, and, because they do so, explanation at the unit levelalone is bound to be misleading. If an approach allows the con-sideration of both unit-level and structural-level causes, then itcan cope with both the changes and the continuities that occur ina system.Structuralrealism presents a systemic portraitof internationalpolitics depicting component units according to the manner oftheir arrangement. For the purpose of developing a theory, statesare cast as unitary actors wanting at least to survive, and are takento be the system's constituent units. The essential structuralqual-ity of the system is anarchy-the absence of a central monopolyof legitimate force. Changes of structure and hence of systemoccur with variations in the number of great powers. The rangeof expected outcomes is inferred from the assumed motivation ofthe units and the structure of the system in which they act.A systems theory of international politics deals with forcesat the international, and not at the national, level. With bothsystems-level and unit-level forces in play, how can one constructa theory of international politics without simultaneously con-structing a theory of foreign policy? An international-politicaltheory does not imply or require a theory of foreign policy anymore than a market theory implies or requires a theory of thefirm. Systems theories, whether political or economic, are theo-ries that explain how the organization of a realm acts as a con-straining and disposing force on the interacting units within it.Such theories tell us about the forces to which the units aresubjected. From them, we can draw some inferences about theexpected behavior and fate of the units: namely, how they willhave to compete with and adjust to one another if they are tosurvive and flourish. To the extent that the dynamics of a systemlimit the freedom of its units, their behavior and the outcomes oftheir behavior become predictable. How do we expect firms torespond to differently structured markets, and states to differentlystructured international-political systems? These theoretical ques-


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WAR IN NEOREALIST THEORY 619tions require us to take firms as firms, and states as states, withoutpaying attention to differences among them. The questions arethen answered by reference to the placement of the units in theirsystem and not by reference to the internal qualities of the units.Systems theories explain why different units behave similarly and,despite their variations, produce outcomes that fall within ex-pected ranges. Conversely, theories at the unit level tell us whydifferent units behave differently despite their similar placementin a system. A theory about foreign policy is a theory at thenational level. It leads to expectations about the responses thatdissimilar polities will make to external pressures. A theory ofinternational politics bears on the foreign policies of nations al-though it claims to explain only certain aspects of them. It cantell us what international conditions national policies have to copewith.

From the vantage point of neorealist theory, competition andconflict among states stem directly from the twin facts of lifeunder conditions of anarchy: States in an anarchic order mustprovide for their own security, and threats or seeming threats totheir security abound. Preoccupation with identifying dangers andcounteracting them become a way of life. Relations remain tense;the actors are usually suspicious and often hostile even though bynature they may not be given to suspicion and hostility. Individ-ually, states may only be doing what they can to bolster theirsecurity. Their individual intentions aside, collectively their ac-tions yield arms races and alliances. The uneasy state of affairs isexacerbated by the familiar "security dilemma," wherein measuresthat enhance one state's security typically diminish that of others.5In an anarchic domain, the source of one's own comfort is thesource of another's worry. Hence a state that is amassing instru-ments of war, even for its own defensive, is cast by others as athreat requiring response. The response itself then serves to con-firm the first state's belief that it had reason to worry. Similarlyan alliance that in the interest of defense moves to increase cohe-sion among its members and add to its ranks inadvertently im-perils an opposing alliance and provokes countermeasures.Some states may hunger for power for power's sake. Neo-realist theory, however, shows that it is not necessary to assume5 SeeJohn H. Herz, "Idealist Internationalism and the Security Dilemma," WorldPolitics,II (I950), I57-I80.


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620 KENNETH N. WALTZan innate lust for power in order to account for the sometimesfierce competition that marks the international arena. In an an-archic domain, a state of war exists if all parties lust for power.But so too will a state of war exist if all states seek only to ensuretheir own safety.

Although neorealist theory does not explain why particularwars are fought, it does explain war's dismal recurrence throughthe millennia. Neorealists point not to the ambitions or the in-trigues that punctuate the outbreak of individual conflicts butinstead to the existing structure within which events, whether bydesign or accident, can precipitate open clashes of arms. Theorigins of hot wars lie in cold wars, and the origins of cold warsare found in the anarchic ordering of the international arena.The recurrence of war is explained by the structure of theinternational system. Theorists explain what historians know:War is normal. Any given war is explained not by looking at thestructure of the international-political system but by looking atthe particularities within it: the situations, the characters, and theinteractions of states. Although particular explanations are foundat the unit level, general explanations are also needed. Wars varyin frequency, and in other ways as well. A central question for astructural theory is this: How do changes of the system affect theexpected frequency of war?KEEPING WARS COLD: THE STRUCTURAL LEVEL In an anarchicrealm, peace is fragile. The prolongation of peace requires thatpotentially destabilizing developments elicit the interest and thecalculated response of some or all of the system's principal actors.In the anarchy of states, the price of inattention or miscalculationis often paid in blood. An important issue for a structural theoryto address is whether destabilizing conditions and events are man-aged better in multipolar or bipolar systems.In a system of, say, five great powers, the politics of powerturns on the diplomacy by which alliances are made, maintained,and disrupted. Flexibility of alignment means both that the coun-try one is wooing may prefer another suitor and that one's presentalliance partner may defect. Flexibility of alignment limits a state'soptions because, ideally, its strategy must please potential alliesand satisfy present partners. Alliances are made by states that havesome but not all of their interests in common. The common


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WAR IN NEOREALIST THEORY 621interest is ordinarily a negative one: fear of other states. Diver-gence comes when positive interests are at issue. In alliancesamong near equals, strategies are always the product of compro-mise since the interests of allies and their notions of how to securethem are never identical.

If competing blocs are seen to be closely balanced, and ifcompetition turns on important matters, then to let one's sidedown risks one's own destruction. In a moment of crisis theweaker or the more adventurous party is likely to determine itsside's policy. Its partners can afford neither to let the weakermember be defeated nor to advertise their disunity by failing toback a venture even while deploring its risks.The prelude to World War I provides striking examples ofsuch a situation. The approximate equality of partners in both theTriple Alliance and Triple Entente made them closely interdepen-dent. This interdependence, combined with the keen competitionbetween the two camps, meant that, although any country couldcommit its associates, no one country on either side could exercisecontrol. If Austria-Hungary marched, Germany had to follow;the dissolution of the Austro-Hungarian Empire would have leftGermany alone in the middle of Europe. If France marched,Russia had to follow; a German victory over France would be adefeat for Russia. And so the vicious circle continued. Becausethe defeat or the defection of a major ally would have shaken thebalance, each state was constrained to adjust its strategy and theuse of its forces to the aims and fears of its partners.In alliances among equals, the defection of one memberthreatens the security of the others. In alliances among unequals,the contributions of the lesser members are at once wanted andof relatively small importance. In alliances among unequals, alli-ance leaders need worry little about the faithfulness of their fol-lowers, who usually have little choice anyway. Contrast the sit-uation in I914 with that of the United States and Britain andFrance in I956. The United States could dissociate itself from theSuez adventure of its two principal allies and subject one of themto heavy financial pressure. Like Austria-Hungary in 1914, Britainand France tried to commit or at least immobilize their ally bypresenting a fait accompli. Enjoying a position of predominance,the United States could continue to focus its attention on themajor adversary while disciplining its two allies. Opposing Brit-


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622 KENNETH N. WALTZain and France endangered neither the United States nor the alli-ance because the security of Britain and France depended muchmore heavily on us than our security depended on them. Theability of the United States, and the inability of Germany, to paya price measured in intra-alliance terms is striking.In balance-of-power politics old style, flexibility of alignmentled to rigidity of strategy or the limitation of freedom of decision.In balance-of-power politics new style, the obverse is true: Rig-idity of alignment in a two-power world results in more flexibilityof strategy and greater freedom of decision. In a multipolar world,roughly equal parties engaged in cooperative endeavors must lookfor the common denominator of their policies. They risk findingthe lowest one and easily end up in the worst of all possibleworlds. In a bipolar world, alliance leaders can design strategiesprimarily to advance their own interests and to cope with theirmain adversary and less to satisfy their own allies.Neither the United States nor the Soviet Union has to seekthe approval of other states, but each has to cope with the other.In the great-power politics of a multipolar world, who is a dangerto whom and who can be expected to deal with threats andproblems are matters of uncertainty. In the great-power politicsof a bipolar world, who is a danger to whom is never in doubt.Any event in the world that involves the fortunes of either of thegreat powers automatically elicits the interest of the other. Pres-ident Harry S. Truman, at the time of the Korean invasion, couldnot very well echo Neville Chamberlain's words in the Czecho-slovakian crisis by claiming that the Americans knew nothingabout the Koreans, a people living far away in the east of Asia.We had to know about them or quickly find out.In a two-power competition, a loss for one is easily taken tobe a gain for the other. As a result, the powers in a bipolar worldpromptly respond to unsettling events. In a multipolar world,dangers are diffused, responsibilities unclear, and definitions ofvital interests easily obscured. Where a number of states are inbalance, the skillful foreign policy of a forward power is designedto gain an advantage without antagonizing other states and fright-ening them into united action. At times in modern Europe, thebenefits of possible gains have seemed to outweigh the risks oflikely losses. Statesmen have hoped to push an issue to the limitwithout causing all of the potential opponents to unite. When


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WAR IN NEOREALIST THEORY | 623there are several possible enemies, unity of action among them isdifficult to achieve. National leaders could therefore think-ordesperately hope, as did Theobald von Bethmann Hollweg andAdolf Hitler before two world wars-that a united oppositionwould not form.If interests and ambitions conflict, the absence of crises ismore worrisome than their presence. Crises are produced by thedetermination of a state to resist a change that another state triesto make. As the leaders in a bipolar system, the United Statesand the Soviet Union are disposed to do the resisting, for inimportant matters they cannot hope that their allies will do it forthem. Political action in the postwar world has reflected thiscondition. Communist guerrillas operating in Greece promptedthe Truman Doctrine. The tightening of Soviet control over thestates of Eastern Europe led to the Marshall Plan and the AtlanticDefense Treaty, and these in turn gave rise to the Cominformand the Warsaw Pact. The plan to create a West German govern-ment produced the Berlin blockade. During the past four decades,our responses have been geared to the Soviet Union's actions,and theirs to ours.Miscalculation by some or all of the great powers is a sourceof danger in a multipolar world; overreaction by either or bothof the great powers is a source of danger in a bipolar world.Which is worse: miscalculation or overreaction? Miscalculation isthe greater evil because it is more likely to permit an unfoldingof events that finally threatens the status quo and brings thepowers to war. Overreaction is the lesser evil because at worst itcosts only money for unnecessary arms and possibly the fightingof limited wars. The dynamics of a bipolar system, moreover,provide a measure of correction. In a world in which two statesunited in their mutual antagonism overshadow any others, thebenefits of a calculated response stand out most clearly, and thesanctions against irresponsible behavior achieve their greatestforce. Thus two states, isolationist by tradition, untutored in theways of international politics, and famed for impulsive behavior,have shown themselves-not always and everywhere, but alwaysin crucial cases-to be wary, alert, cautious, flexible, and for-bearing.Moreover, the economies of the great powers in a bipolarworld are less interdependent than those of the great powers of a


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624 KENNETH N. WALTZmultipolar one. The size of great powers tends to increase as theirnumbers fall, and the larger a state is, the greater the variety ofits resources. States of continental size do proportionately less oftheir business abroad than, for example, Britain, France, andGermany did in their heydays. Never before in modern historyhave the great powers depended so little on the outside world,and been so uninvolved in one another's economic affairs, as theUnited States and the Soviet Union have been since the war. Theseparation of their interests reduces the occasions for dispute andpermits them, if they wish, to leave each other alone even thougheach defines its security interests largely in terms of the other.Interdependence of parties, diffusion of dangers, confusionof responses: These are the characteristics of great-power politicsin a multipolar world. Self-dependence of parties, clarity of dan-gers, certainty about who has to face them: These are the char-acteristics of great-power politics in a bipolar world.

KEEPING WARS COLD: THE UNIT LEVEL A major reason for theprolongation of the postwar peace is the destruction of the oldmultipolar world in World War II and its replacement by a bipolarone. In a bipolar world, we expect competition to be keen, yetmanageable. But to believe that bipolarity alone accounts for the"long peace" between the United States and the Soviet Union isdifficult. Given the depth and extent of the distrust felt by bothparties, one may easily believe that one or another of the crisesthat they have experienced would, in earlier times, have drawnthem into war. For a fuller explanation of why that did nothappen, we must look to that other great force for peace: nuclearweapons.States continue to coexist in an anarchic order. Self-help isthe principle of action in such an order, and the most importantway in which states must help themselves is by providing fortheir own security. Therefore, in weighing the chances of peace,the first questions to ask are questions about the ends for whichstates use force and about the strategies and weapons they employ.The chances of peace rise if states can achieve their most importantends without actively using force. War becomes less likely as thecosts of war rise in relation to the possible gains. Realist theory,old and new alike, draws attention to the crucial role of military


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WAR IN NEOREALIST THEORY 625technology and strategy among the forces that fix the fate of statesand their systems.

Nuclear weapons dissuade states from going to war muchmore surely than conventional weapons do. In a conventionalworld, states can believe both that they may win and that, shouldthey lose, the price of defeat will be bearable, although WorldWars I and II called the latter belief into question even beforeatomic bombs were dropped. If the United States and the SovietUnion were now armed only with conventional weapons, thelessons of those wars would be clearly remembered, especially bythe Soviet Union, which suffered more in war than the UnitedStates. Had the atom never been split, those two nations wouldstill have much to fear from each other. Armed with increasinglydestructive conventional weapons, they would be constrained tostrive earnestly to avoid war. Yet, in a conventional world, evensad and strong lessons like those of the two world wars haveproved exceedingly difficult for states to learn. Throughout mod-ern history, one great power or another has looked as though itmight become dangerously strong: for example, France underLouis XIV and Napoleon Bonaparte, and Germany under Wil-helm II and Hitler. In each case, an opposing coalition formedand turned the expansive state back. The lessons of history wouldseem to be clear: In international politics, success leads to failure.The excessive accumulation of power by one state or coalition ofstates elicits the opposition of others. The leaders of expansioniststates have nevertheless been able to persuade themselves thatskillful diplomacy and clever strategy would enable them to tran-scend the normal processes of balance-of-power politics.The experience of World War II, bipolarity, and the increaseddestructiveness of conventional weapons would make World WarIII more difficult to start than earlier wars were; and the presenceof nuclear weapons dramatically increases that difficulty. Nuclearweapons reverse or negate many of the conventional causes ofwar. Wars can be fought in the face of nuclear weapons, but thehigher the stakes and the closer a country comes to winning them,the more surely that country invites retaliation and risks its owndestruction. The accumulation of significant power through con-quest, even if only conventional weapons are used, is no longerpossible in the world of nuclear powers. Those individuals whobelieve that the Soviet Union's leaders are so bent on world


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626 KENNETH N. WALTZdomination that they may be willing to run catastrophic risks forproblematic gains fail to understand how governments behave.Do we expect to lose one city or two? Two cities or ten? Whenthese are the pertinent questions, political leaders stop thinkingabout running risks and start worrying about how to avoid them.Deterrence is more easily achieved than most military strat-egists would have us believe. In a conventional world, a countrycan sensibly attack if it believes that success is probable. In anuclear world, a country cannot sensibly attack unless it believesthat success is assured. A nation will be deterred from attackingeven if it believes that there is only a possibility that its adversarywill retaliate. Uncertainty of response, not certainty, is requiredfor deterrence because, if retaliation occurs, one risks losing all.As Clausewitz wrote: If war approaches the absolute, it becomesimperative "not to take the first step without thinking what maybe the last."6

Nuclear weapons make the implications even of victory toohorrible to contemplate. The problem that the nuclear powersmust solve is how to perpetuate peace when it is not possible toeliminate all of the causes of war. The structure of internationalpolitics has not been transformed; it remains anarchic in form.Nuclear states continue to compete militarily. With each statestriving to ensure its own security, war remains constantly pos-sible. In the anarchy of states, improving the means of defenseand deterrence relative to the means of offense increases thechances of peace. Weapons and strategies that make defense anddeterrence easier, and offensive strikes harder to mount, decreasethe likelihood of war.7Although the possibility of war remains, the probability ofa war involving states with nuclear weapons has been drasticallyreduced. Over the centuries great powers have fought more warsthan minor states, and the frequency of war has correlated moreclosely with a structural characteristic-their international stand-ing-than with unit-level attributes. Yet, because of a change inmilitary technology, a change at the unit level, waging war has6 Karl von Clausewitz (ed. Anatol Rapaport; trans.J. J. Graham), On War Hammond-sworth, I968), V, 374.7 See Malcolm W. Hoag, "On Stability in Deterrent Races," in Morton A. Kaplan (ed.),The Revolution n WorldPolitics (New York, 1962), 388-4IO; Robert Jervis, "Cooperationunder the Security Dilemma," WorldPolitics,XXX (I978), I67-214.


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WAR IN NEOREALIST THEORY | 627increasingly become the privilege of poor and weak states. Nu-clear weapons have banished war from the center of internationalpolitics. A unit-level change has dramaticallyreduced a structuraleffect.The probability of major war among states having nuclearweapons approaches zero. But the "real war" may, as Jamesclaimed, lie in the preparations for waging it. The logic of adeterrent strategy, if it is followed, also circumscribes the causesof "real wars."8 In a conventional world, the structure of inter-national politics encourages states to arm competitively. In a nu-clear world, deterrent strategies offer the possibility of dampeningthe competition. Conventional weapons are relative. With con-ventionl weapons, competing countries must constantly comparetheir strengths. How secure a country is depends on how itcompares to others in the quantity and quality of its weaponry,the suitability of its strategy, the resilience of its society andeconomy, and the skill of its leaders.Nuclear weapons are not relative but absolute weapons.9They make it possible for a state to limit the size of its strategicforces so long as other states are unable to achieve disarming first-strike capabilities by improving their forces. If no state can launcha disarming attack with high confidence, comparing the size ofstrategic forces becomes irrelevant. For deterrence, one asks howmuch is enough, and enough is defined as a second-strike capa-bility. This interpretation does not imply that a deterrent forcecan deter everything, but rather that, beyond a certain level,additional forces provide no additional security for one party andpose no additional threat to others. The two principal powers inthe system have long had second-strike forces, with neither ableto launch a disarming strike against the other. That both never-theless continue to pile weapon upon unneeded weapon is a puzzlewhose solution can be found only within the United States andthe Soviet Union.WARS, HOT AND COLD Wars, hot and cold, originate in thestructure of the international political system. Most Americans8 William James, "The Moral Equivalent of War," in Leon Bramson and George W.Goethals (eds.), War:StudiesfromPsychology,Sociology,andAnthropologyNew York, I968;rev. ed.), 23.9 Cf. Bernard Brodie, The Absolute Weapon:Atomic Powerand WorldOrder(New York,1946), 75-76.


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628 KENNETH N. WALTZblame the Soviet Union for creating the Cold War, by the actionsthat follow necessarily from the nature of its society and govern-ment. Revisionist historians, attacking the dominant view, assignblame to the United States. Some American error, or sinisterinterest, or faulty assumption about Soviet aims, they argue, iswhat started the Cold War. Either way, the main point is lost. Ina bipolar world, each of the two great powers is bound to focusits fears on the other, to distrust its motives, and to imputeoffensive intentions to defensive measures. The proper questionis what, not who, started the Cold War. Although its content andvirulence vary as unit-level forces change and interact, the ColdWar continues. It is firmly rooted in the structure of postwarinternational politics, and will last as long as that structure en-dures.

In any closely competitive system, it may seem that one iseither paranoid or a loser. The many Americans who ascribeparanoia to the Soviet Union are saying little about its politicalelite and much about the international-political system. Yet, inthe presence of nuclear weapons, the Cold War has not becomea hot one, a raging war among major states. Constraints onfighting big wars have bound the major nuclear states into asystem of uneasy peace. Hot wars originate in the structure ofinternational politics. So does the Cold War, with its temperaturekept low by the presence of nuclear weapons.

waltz - origins of war

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