CAMBRIDGE UNIVERSITY PRESS The Kantian Peace:The Pacific Benefits of Democracy,Interdependence,and International Organizations,1885-1992 Author(s):John R.Oneal and Bruce Russett Source:World Politics,Vol.52,No.1 (Oct.,1999).pp.1-37 Published by:Cambridge University Press Stable URL:http://www.jstor.org/stable/25054099 Accessed:20/08/201019:10 Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use,available at http://www.jstor.org/page/info/about/policies/terms jsp.JSTOR's Terms and Conditions of Use provides,in part,that unless you have obtained prior permission,you may not download an entire issue of a journal or multiple copies of articles,and you may use content in the JSTOR archive only for your personal,non-commercial use. Please contact the publisher regarding any further use of this work.Publisher contact information may be obtained at http://www.jstor.org/action/showPublisher?publisherCode=cup. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. JSTOR is a not-for-profit service that helps scholars,researchers,and students discover,use,and build upon a wide range of content in a trusted digital archive.We use information technology and tools to increase productivity and facilitate new forms of scholarship.For more information about JSTOR,please contact support@jstor.org. Cambridge University Press is collaborating with JSTOR to digitize,preserve and extend access to World Politics. STOR http://www.jstor.org
The Kantian Peace: The Pacific Benefits of Democracy, Interdependence, and International Organizations, 1885-1992 Author(s): John R. Oneal and Bruce Russett Source: World Politics, Vol. 52, No. 1 (Oct., 1999), pp. 1-37 Published by: Cambridge University Press Stable URL: http://www.jstor.org/stable/25054099 Accessed: 20/08/2010 19:10 Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use. Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at http://www.jstor.org/action/showPublisher?publisherCode=cup. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. Cambridge University Press is collaborating with JSTOR to digitize, preserve and extend access to World Politics. http://www.jstor.org
THE KANTIAN PEACE The Pacific Benefits of Democracy, Interdependence,and International Organizations,1885-1992 By JOHN R.ONEAL and BRUCE RUSSETT* TUST over two hundred years ago Immanuel Kant suggested that"re- publican constitutions,"a"commercial spirit"of international trade, and a federation of interdependent republics would provide the basis for perpetual peace.The alternative,even starker in the nuclear era than in 1795,would be peace of a different sort:"a vast grave where all the horrors of violence and those responsible for them would be buried." Consequently,Kant declared,we have a duty to work for peaceful in- ternational relations.Though he emphasized the absolute character of this moral imperative,he was no idealist;rather,he believed that natu- ral processes based on self-interest impelled individuals to act in ways that would eventually produce a lasting and just peace.Kant was also realistic.He acknowledged that war was inherent in the anarchic inter- national system and therefore cautioned that nations must act pru- dently until the federation of interdependent republics was established. But he also knew that the mechanisms of power politics produce only temporary respite from conflict,not lasting solutions. Over the past half century much of the world has been at peace.Un- derstanding that phenomenon,its causes and trajectory,is the funda- mental challenge for international relations scholars today.We seek to show that Kant's realistic statement of liberal theory provides useful guidance for this task.Most political scientists now agree that the con- temporary peacefulness can be traced in part to the so-called demo- cratic peace,wherein established democratic states have fought no We thank the Carnegie Corporation of New York,the Ford Foundation,and the National Sci- ence Foundation for financial support;Zeev Maoz for comments;and Jennifer Beam,Margit Buss- mann,Soo Yeon Kim,Yury Omelchenko,Brian Radigan,and Jacob Sullivan for data collection and management. 1Kant,Perpetual Peace:A Philosopbical Sketch,in Kant's Political Writings,ed.Hans Reiss (Cam- bridge:Cambridge University Press,1970),105.See also James Bohman and Matthias Lutz-Bach- mann,eds.,Perpetual Peace:Essays on Kant's Cosmopolitan Ideal (Cambridge:MIT Press,1997). World Politics 52(October 1999),1-37
THE KANTIAN PEACE The Pacific Benefits of Democracy, Interdependence, and International Organizations, 1885-1992 By JOHN R. ONEAL and BRUCE RUSSETT* JUST over two hundred years ago Immanuel Kant suggested that "re publican constitutions," a "commercial spirit" of international trade, and a federation of interdependent republics would provide the basis for perpetual peace. The alternative, even starker in the nuclear era than in 1795, would be peace of a different sort: "a vast grave where all the horrors of violence and those responsible for them would be buried."1 Consequently, Kant declared, we have a duty to work for peaceful in ternational relations. Though he emphasized the absolute character of this moral imperative, he was no idealist; rather, he believed that natu ral processes based on self-interest impelled individuals to act in ways that would eventually produce a lasting and just peace. Kant was also realistic. He acknowledged that war was inherent in the anarchic inter national system and therefore cautioned that nations must act pru dently until the federation of interdependent republics was established. But he also knew that the mechanisms of power politics produce only temporary respite from conflict, not lasting solutions. Over the past half century much of the world has been at peace. Un derstanding that phenomenon, its causes and trajectory, is the funda mental challenge for international relations scholars today. We seek to show that Kant s realistic statement of liberal theory provides useful guidance for this task. Most political scientists now agree that the con temporary peacefulness can be traced in part to the so-called demo cratic peace, wherein established democratic states have fought no * We thank the Carnegie Corporation of New York, the Ford Foundation, and the National Sci ence Foundation for financial support; Zeev Maoz for comments; and Jennifer Beam, Margit Buss mann, Soo Yeon Kim, Yury Omelchenko, Brian Radigan, and Jacob Sullivan for data collection and management. 1Kant, Perpetual Peace: A Philosophical Sketch, in Kants Political Writings, ed. Hans Reiss (Cam bridge: Cambridge University Press, 1970), 105. See also James Bohman and Matthias Lutz-Bach mann, eds., Perpetual Peace: Essays on Kants Cosmopolitan Zafe?/(Cambridge: MIT Press, 1997). World Politics 52 (October 1999), 1-37
2 WORLD POLITICS international wars with one another and the use or threat of force among them,even at low levels,has been rare.2 This view is incomplete, however,because it fails to recognize the pacific benefits of the other lib- eral elements of Kant's program for peace.Moreover,the term hides the vigorous theoretical controversy about the processes underlying this sep- arate peace-over whether democracy is really even its cause and over the degree to which the empirical phenomenon existed in other eras. These theoretical and empirical concerns are linked.If,for example, peaceful relations among democracies during the cold war era were simply a consequence of their shared security interests vis-a-vis the op- posing alliance system in a bipolar world,then their peacefulness would be spuriously related to the character of their regimes.The same con- clusion would result if the democratic peace could be attributed to the hegemonic power of the United States to suppress conflict among its allies or to East-West differences in preferences unrelated to underlying differences in regimes.3 One would not then expect to find a separate peace among democratic states in other periods evincing different pat- terns of interstate relations.We address these questions by reporting analyses covering 1885-1992,to show that peaceful relations among democracies existed throughout the twentieth century.4 Extending the historical domain also allows us to assess the effect of the changing character of the international system on interstate relations.5 2 By convention in the social science literature,war is defined as a conflict between two recognized sovereign members of the international system that results in at least one thousand battle deaths.The most complete data on militarized international disputes (MIDs),compiled by Stuart Bremer and his colleagues,are available at http://pss.la-psu.edu/MID_DATA.HTM.The democracy data we employ were compiled by Keith Jaggers and Ted Robert Gurr,"Tracking Democracy's Third Wave with the Polity III Data,"Journal of Peace Research 32,no.4(1995),available at http://iscre.colorado.cdu- /pub/datasets/polity3/politymay96.data.Both data sets are produced independently from the demo- cratic peace research program,and the initial codings,from the 1980s,precede it.Reviews of the program include Steve Chan,"In Search of Democratic Peace:Problems and Promise,"Mershon Inter- national Studies Review 41,no.1(1997);James Lee Ray,"Does Democracy Cause Peace?"Annual Review of Political Science 1(1997);and Bruce Russett and Harvey Starr,"From Democratic Peace to Kantian Peace:Democracy and Confict in the International System,"in Manus Midlarsky,ed.,Handboo ofWar Studies,2d ed.(Ann Arbor:University of Michigan Press,forthcoming). 3 Henry Farber and Joanne Gowa,"Common Interests or Common Polities?"Journal of Politics 57,no. 2(1997);Gowa,Ballots and Bullets:The Elusive Democratic Peace (Princeton:Princeton University Press, 1999);Douglas Lemke and William Reed,"Regime Types and Status Quo Evaluations,"International Interactions 22,no.2(1996);Erik Gartzke,"Kant We All Just Get Along?Opportunity,Willingness and the Origins of the Democratic Peace,"American Journal of Political Science 42,no.1 (1998). The MIDs data(fn.2)are unavailable after 1992,and data on dyadic trade are sparse and unreliable before 1885.In any event the further back one goes into the nineteenth century,the rarer are instances of democracy,intergovernmental organizations,and high levels of economic interdependence.The MIDs data include only disputes between recognized states and not,for example,extrasystemic(ie.,colonial) actions,covert operations,or domestic military interventions in support of a recognized government. s We will not here offer a new theory on why democracy produces peaceful relations.A recent state- ment is Bruce Bueno de Mesquita et al,An Institutional Explanation of the Democratic Peace," American Political Science Review 93,no.4 (1999)
2 WORLD POLITICS international wars with one another and the use or threat of force among them, even at low levels, has been rare.2 This view is incomplete, however, because it fails to recognize the pacific benefits of the other lib eral elements of Kant s program for peace. Moreover, the term hides the vigorous theoretical controversy about the processes underlying this sep arate peace?over whether democracy is really even its cause and over the degree to which the empirical phenomenon existed in other eras. These theoretical and empirical concerns are linked. If, for example, peaceful relations among democracies during the cold war era were simply a consequence of their shared security interests vis-?-vis the op posing alliance system in a bipolar world, then their peacefulness would be spuriously related to the character of their regimes. The same con clusion would result if the democratic peace could be attributed to the hegemonic power of the United States to suppress conflict among its allies or to East-West differences in preferences unrelated to underlying differences in regimes.3 One would not then expect to find a separate peace among democratic states in other periods evincing different pat terns of interstate relations. We address these questions by reporting analyses covering 1885-1992, to show that peaceful relations among democracies existed throughout the twentieth century4 Extending the historical domain also allows us to assess the effect of the changing character of the international system on interstate relations.5 2 By convention in the social science literature, war is defined as a conflict between two recognized sovereign members of the international system that results in at least one thousand battle deaths. The most complete data on militarized international disputes (MIDs), compiled by Stuart Bremer and his colleagues, are available at http://pss.la.psu.edu/MID_DATA.HTM. The democracy data we employ were compiled by Keith Jaggers and Ted Robert Gurr, "Tracking Democracy's Third Wave with the Polity III Data,"Journalof* Peace Research 32, no. 4 (1995), available at http://isere.colorado.edu /pub/datasets/polity3/politymay96.data. Both data sets are produced independently from the demo cratic peace research program, and the initial codings, from the 1980s, precede it. Reviews of the program include Steve Chan, "In Search of Democratic Peace: Problems and Promise," Mershon Inter national Studies Review 41, no. 1 (1997); James Lee Ray, "Does Democracy Cause Peace?" Annual Review of Political Science 1 (1997); and Bruce Russett and Harvey Starr, "From Democratic Peace to Kantian Peace: Democracy and Conflict in the International System," in Manus Midlarsky, ed., Handbook of War Studies, 2d ed. (Ann Arbor: University of Michigan Press, forthcoming). 3 Henry F?rber and Joanne Gowa, "Common Interests or Common Polities?" Journal of Politics 57, no. 2 (1997); Gowa, Ballots and Bullets: The Elusive Democratic Peace (Princeton: Princeton University Press, 1999); Douglas Lemke and William Reed, "Regime Types and Status Quo Evaluations," International Interactions 22, no. 2 (1996); Erik Gartzke, "Kant We All Just Get Along? Opportunity, Willingness and the Origins of the Democratic Peace,"American JournalofPoliticalScience 42, no. 1 (1998). 4 The MIDs data (fn. 2) are unavailable after 1992, and data on dyadic trade are sparse and unreliable before 1885. In any event the further back one goes into the nineteenth century, the rarer are instances of democracy, intergovernmental organizations, and high levels of economic interdependence. The MIDs data include only disputes between recognized states and not, for example, extrasystemic (i.e., colonial) actions, covert operations, or domestic military interventions in support of a recognized government. 5 We will not here offer a new theory on why democracy produces peaceful relations. A recent state ment is Bruce Bueno de Mesquita et al., "An Institutional Explanation of the Democratic Peace," American Political Science Review 93, no. 4 (1999)
KANTIAN PEACE 3 In keeping with the Kantian perspective,we expand our analysis be- yond the democratic peace,incorporating the influence of economically important trade and joint memberships in international organizations. The classical liberals of the eighteenth and nineteenth centuries ex- pected interdependence as well as popular control of government to have important pacific benefits.Commercial relations draw states into a web of mutual self-interest that constrains them from using force against one another.Thus interdependence and democracy contribute to what we have called the"liberal peace."Kant emphasized,in addi- tion,the benefits of international law and organization.Our previous analyses of the cold war era indicate that,during those years at least, trade and networks of intergovernmental organizations did reduce the number of militarized interstate disputes;these effects were on top of the benefits of democracy.6 We show here that they also operated in earlier and later years. OUR OBJECTIVES AND METHOD Although the liberal and realist perspectives are often considered anti- thetical,in keeping with Kant's philosophical analysis we conduct our tests of the Kantian peace while taking into account important realist influences.We believe,as Kant did,that both perspectives matter,as 6 John R.Oneal and Bruce Russett,"The Classical Liberals Were Right:Democracy,Interdepen- dence,and Conflict,1950-1985,"International Studies Quarterly 40,no.2(1997);Russett,Oneal,and David R.Davis,"The Third Leg of the Kantian Tripod:International Organizations and Militarized Disputes,1950-85,"International Organization 52,no.3(1998);Oneal and Russett,"Assessing the Liberal Peace with Alternative Specifications:Trade Still Reduces Conflict,"Journal of Peace Researcb 36,no.4(1999).Here we extend this line of research in three ways:(1)providing a conceptual syn- thesis of Kantian and realist theories that treats conflict as inherent but subject to important con- straints;(2)extending the temporal domain for trade and IGos into the nineteenth century;and(3) assessing realist theories regarding the role of the hegemon and Kantian theories about systemic influ- ences in a way that addresses,among others,constructivist and evolutionary perspectives on the inter- national system.Note that the Kantian influences may be mutually reinforcing in a dynamic system of feedback loops,as suggested by Wade Huntley,"Kant's Third Image:Systemic Sources of the Liberal Peace,"International Studies Quarterly 40,no.4(1996);and Russett,"A Neo-Kantian Perspective:De- mocracy,Interdependence,and International Organizations in Building Security Communities,"in Emanuel Adler and Michacl Barnett,eds.,Security Communities in Comparative Perspective (New York: Cambridge University Press,1998). We and others have begun to address some of these links,such as greater trade between democra- cies,the possibility that trade is diminished between conflicting states,the effect of democracy,trade, and peace in increasing membership in international organizations,and the effect of conflict on de- mocracy.On the first,see Harry Bliss and Russett,"Democratic Trading Partners:The Liberal Con- nection,"Journal of Politics 58,no.4(1998),and James Morrow,Randolph Siverson,and Tessa Tabares, "The Political Determinants of International Trade:The Major Powers,1907-90,"American Political Science Review 92,no.3(1998);on the second,see Soo Yeon Kim,"Ties That Bind:The Role of Trade in International Conflict Processes"(Ph.D.diss.,Yale University,1998);on the third,see Russett,Oneal, and Davis(this fn.);and on the last,see Oneal and Russett,"Why 'An Identified Systemic Model of the Democratic Peace Nexus'Does Not Persuade,"Defence and Peace Economics 11,no.2(2000)
KANTIAN PEACE 3 In keeping with the Kantian perspective, we expand our analysis be yond the democratic peace, incorporating the influence of economically important trade and joint memberships in international organizations. The classical liberals of the eighteenth and nineteenth centuries ex pected interdependence as well as popular control of government to have important pacific benefits. Commercial relations draw states into a web of mutual self-interest that constrains them from using force against one another. Thus interdependence and democracy contribute to what we have called the "liberal peace." Kant emphasized, in addi tion, the benefits of international law and organization. Our previous analyses of the cold war era indicate that, during those years at least, trade and networks of intergovernmental organizations did reduce the number of militarized interstate disputes; these effects were on top of the benefits of democracy.6 We show here that they also operated in earlier and later years. Our Objectives and Method Although the liberal and realist perspectives are often considered anti thetical, in keeping with Kant s philosophical analysis we conduct our tests of the Kantian peace while taking into account important realist influences. We believe, as Kant did, that both perspectives matter, as 6 John R. Oneal and Bruce Russett, "The Classical Liberals Were Right: Democracy, Interdepen dence, and Conflict, 1950-1985," International Studies Quarterly 40, no. 2 (1997); Russett, Oneal, and David R. Davis, "The Third Leg of the Kantian Tripod: International Organizations and Militarized Disputes, 1950-85," International Organization 52, no. 3 (1998); Oneal and Russett, "Assessing the Liberal Peace with Alternative Specifications: Trade Still Reduces Conflict," fournal of Peace Research 36, no. 4 (1999). Here we extend this line of research in three ways: (1) providing a conceptual syn thesis of Kantian and realist theories that treats conflict as inherent but subject to important con straints; (2) extending the temporal domain for trade and IGOs into the nineteenth century; and (3) assessing realist theories regarding the role of the hegemon and Kantian theories about systemic influ ences in a way that addresses, among others, constructivist and evolutionary perspectives on the inter national system. Note that the Kantian influences may be mutually reinforcing in a dynamic system of feedback loops, as suggested by Wade Hundey, "Kant's Third Image: Systemic Sources of the Liberal Peace," International Studies Quarterly 40, no. 4 (1996); and Russett, "A Neo-Kantian Perspective: De mocracy, Interdependence, and International Organizations in Building Security Communities," in Emanuel Adler and Michael Barnett, eds., Security Communities in Comparative Perspective (New York Cambridge University Press, 1998). We and others have begun to address some of these links, such as greater trade between democra cies, the possibility that trade is diminished between conflicting states, the effect of democracy, trade, and peace in increasing membership in international organizations, and the effect of conflict on de mocracy. On the first, see Harry Bliss and Russett, "Democratic Trading Partners: The Liberal Con nection,"fournal of Politics 58, no. 4 (1998), and James Morrow, Randolph Siverson, and Tessa Tabares, "The Political Determinants of International Trade: The Major Powers, 1907-90," American Political Science Review 92, no. 3 (1998); on the second, see Soo Yeon Kim, "Ties That Bind: The Role of Trade in International Conflict Processes" (Ph.D. diss., Yale University, 1998); on the third, see Russett, Oneal, and Davis (this fn.); and on the last, see Oneal and Russett, "Why An Identified Systemic Model of the Democratic Peace Nexus' Does Not Persuade," Defence and Peace Economics 11, no. 2 (2000)
WORLD POLITICS both consider conflict and the threat of violence to be inherent in an anarchic world of sovereign states.The Hobbesian element of this un- derstanding is central to realist theory,but it is also deeply embedded in the liberal tradition.Kant accepted Hobbes's description of a state of war among nations and believed that a balance of power could prevent war;but history has shown all too clearly,as most realists acknowledge, that this peace"is tenuous.Kant,however,was convinced that a gen- uine,positive peace could be developed within a"federation"of liberal republics that rested more on the three Kantian supports-democracy, interdependence,and international law and organizations-than on power politics.The pacific federation envisioned by Kant is not a world state but a federation whose members remain sovereign,linked only by confederational or collective security arrangements.Liberalism,that is, sees democratic governance,economic interdependence,and interna- tional law as the means by which to supersede the security dilemma rooted in the anarchy of the international system.For states not much linked by these ties,however,the threat of violence remains.In addi- tion,liberal states must fear those illiberal states that remain outside the Kantian confederation.? Thus we begin by assuming that the international system is anarchic and power is important.Yet despite the inherent possibility of violence, states do not fight all others or at all times even where realist principles dominate.Rather,they are constrained by power,alliances,and dis- tance.States must be concerned with the balance of power and the co- incidence of national interests expressed in alliances.Many states, moreover,are irrelevant to these calculations:in general,the farther apart two states are,the fewer are the issues over which to fight and the less the threat they pose to one another.Ultimately therefore realists are concerned only with states that have the opportunity and incentive to engage in conflict.8 Accordingly because these constraints provide a baseline against which to assess the additional impact of the Kantian influences,we incorporate them as central features of our theoretical model.To the realist variables we add measures for the three Kantian constraints,hypothesizing that(1)democracies will use force less fre- quently,especially against other democracies;(2)economically impor- tant trade creates incentives for the maintenance of peaceful relations; Michael W.Doyle,Ways of War and Peace (New York:W.W.Norton,1997),chap.8;David Lake, "Powerful Pacifists:Democratic States and War,"American Political Science Review 86,no.4(1992). Birger Heldt,"Inherency,Contingency,and Theories of Conflict and Peace"(Manuscript,Yale University,1998);Benjamin Most and Harvey Start,Inguiry,Logic,and International Politics(Colum- bia:University of South Carolina Press,1989),chap.2
4 WORLD POLITICS both consider conflict and the threat of violence to be inherent in an anarchic world of sovereign states. The Hobbesian element of this un derstanding is central to realist theory, but it is also deeply embedded in the liberal tradition. Kant accepted Hobbes's description of a state of war among nations and believed that a balance of power could prevent war; but history has shown all too clearly, as most realists acknowledge, that this "peace" is tenuous. Kant, however, was convinced that a gen uine, positive peace could be developed within a "federation" of liberal republics that rested more on the three Kantian supports?democracy, interdependence, and international law and organizations?than on power politics. The pacific federation envisioned by Kant is not a world state but a federation whose members remain sovereign, linked only by confederation^ or collective security arrangements. Liberalism, that is, sees democratic governance, economic interdependence, and interna tional law as the means by which to supersede the security dilemma rooted in the anarchy of the international system. For states not much linked by these ties, however, the threat of violence remains. In addi tion, liberal states must fear those illiberal states that remain outside the Kantian confederation.7 Thus we begin by assuming that the international system is anarchic and power is important. Yet despite the inherent possibility of violence, states do not fight all others or at all times even where realist principles dominate. Rather, they are constrained by power, alliances, and dis tance. States must be concerned with the balance of power and the co incidence of national interests expressed in alliances. Many states, moreover, are irrelevant to these calculations: in general, the farther apart two states are, the fewer are the issues over which to fight and the less the threat they pose to one another. Ultimately therefore realists are concerned only with states that have the opportunity and incentive to engage in conflict.8 Accordingly because these constraints provide a baseline against which to assess the additional impact of the Kantian influences, we incorporate them as central features of our theoretical model. To the realist variables we add measures for the three Kantian constraints, hypothesizing that (1) democracies will use force less fre quently, especially against other democracies; (2) economically impor tant trade creates incentives for the maintenance of peaceful relations; 7 Michael W. Doyle, Ways of War and Peace (New York W. W. Norton, 1997), chap. 8; David Lake, "Powerful Pacifists: Democratic States and War " American Political Science Review 86, no. 4 (1992). 8 Birger Heldt, "Inherency, Contingency, and Theories of Conflict and Peace" (Manuscript, Yale University, 1998); Benjamin Most and Harvey Starr, Inquiry, Logic, and International Politics (Colum bia: University of South Carolina Press, 1989), chap. 2
KANTIAN PEACE S and(3)international organizations constrain decision makers by pro- moting peace in a variety of ways.Since the modern international sys- tem is far from a pacific federation of democratic states,we expect both realist and Kantian factors to affect interstate relations.We explicitly consider how realist and liberal influences at both the dyadic and the systemic level have altered the functioning of the international system, addressing the role of the leading state and the influence of the chang- ing Kantian variables over time. Evidence for the pacific benefits of economic interdependence and membership in intergovernmental organizations(IGOs)is less widely accepted than is that for the democratic peace,and it has been sub- jected to less extensive critical scrutiny.We alone have assessed the ef- fect of IGOs on confict at the dyadic level of analysis.Moreover, theoretical expectations regarding the impact of trade and IGOs are more diverse than those concerning democracy.No one hypothesizes that democracies are more likely to fight each other than are other poli- ties;but the liberal view of the pacific effects of trade is contradicted by those who expect confict over the division of the gains from trade and by the dependency school and its intellectual predecessors and descen- dants,who expect conflict between large and small states.As for IGOs, a plausible view might be that states form or join international organi- zations to manage-albeit often without success-disputes with their adversaries,the UN being an example.More commonly,realists regard international institutions as nearly irrelevant to the security issues at the heart of high politics,with no effect independent of existing power re- lations.10 Even among those who hold that trade or IGOs play a positive role in promoting peace,the reasons advanced vary.Rational choice theorists emphasize political actors'complementary economic interests in maintaining peaceful interstate relations-interests that are reflected in the decisions of national leaders.Fearful of the domestic political consequences of losing the benefits of trade,policymakers avoid the use of force against states with which they engage in economically impor- tant trade.But one can also devise constructivist explanations about how the communication associated with trade builds cross-national sentiments of shared identity.11 A useful review is Susan McMillan,"Interdependence and Conflict,"Mershon International Stud- ies Review 41,no.1(1997). 10 John Mearsheimer,"The False Promise of International Institutions,"International Security 19 (Vinter199495). 1 Emanuel Adler and Michael Barnett,"Security Communities in Theoretical Perspective,"in Adler and Barnett(fn.6);Alexander Wendt,Social Theory of International Politics (New York:Cam- bridge University Press,1999).For microlevel evidence that trading contacts expand elites'views of
KANTIAN PEACE 5 and (3) international organizations constrain decision makers by pro moting peace in a variety of ways. Since the modern international sys tem is far from a pacific federation of democratic states, we expect both realist and Kantian factors to affect interstate relations. We explicitly consider how realist and liberal influences at both the dyadic and the systemic level have altered the functioning of the international system, addressing the role of the leading state and the influence of the chang ing Kantian variables over time. Evidence for the pacific benefits of economic interdependence and membership in intergovernmental organizations (iGOs) is less widely accepted than is that for the democratic peace, and it has been sub jected to less extensive critical scrutiny. We alone have assessed the ef fect of IGOs on conflict at the dyadic level of analysis. Moreover, theoretical expectations regarding the impact of trade and IGOs are more diverse than those concerning democracy. No one hypothesizes that democracies are more likely to fight each other than are other poli ties; but the liberal view of the pacific effects of trade is contradicted by those who expect conflict over the division of the gains from trade and by the dependency school and its intellectual predecessors and descen dants, who expect conflict between large and small states.9 As for IGOs, a plausible view might be that states form or join international organi zations to manage?albeit often without success?disputes with their adversaries, the UN being an example. More commonly, realists regard international institutions as nearly irrelevant to the security issues at the heart of high politics, with no effect independent of existing power re lations.10 Even among those who hold that trade or IGOs play a positive role in promoting peace, the reasons advanced vary. Rational choice theorists emphasize political actors' complementary economic interests in maintaining peaceful interstate relations?interests that are reflected in the decisions of national leaders. Fearful of the domestic political consequences of losing the benefits of trade, policymakers avoid the use of force against states with which they engage in economically impor tant trade. But one can also devise constructivist explanations about how the communication associated with trade builds cross-national sentiments of shared identity.11 9 A useful review is Susan McMillan, "Interdependence and Conflict," Mershon International Stud ies Review 41, no. 1 (1997). 10 John Mearsheimer, "The False Promise of International Institutions," International Security 19 (Winter 1994-95). 11 Emanuel Adler and Michael Barnett, "Security Communities in Theoretical Perspective," in Adler and Barnett (fn. 6); Alexander Wendt, Social Theory of International Politics (New York Cam bridge University Press, 1999). For microlevel evidence that trading contacts expand elites' views of
6 WORLD POLITICS Even realists acknowledge that international institutions like NATO help to preserve peace among their members by supplementing the de- terrent effect of sheer military power.Liberals emphasize the potential of institutions for communicating information and facilitating bargain- ing,12 while constructivists see institutions as instruments for expand- ing people's conceptions of identity,relatedness,and self-interest. Because IGOs vary widely in their functions and capabilities,any or all of these explanations may be correct in a particular instance.13 As with the consequences of democratic institutions,we do not attempt to re- solve these theoretical debates here.Instead we seek to offer an empir- ical assessment of the effect of the Kantian influences on interstate relations. In expanding the historical domain of the Kantian peace,one en- counters hurdles(and opportunities)that arise from marked changes in the nature of political regimes,the importance of international trade, and the role of international organizations.As measured by the stan- dard data on political regimes,Polity III,14 the average level of democ- racy in the international system has risen since the early 1800s,in a pattern that is sporadic and wavelike.15 Similarly,the mean level of eco- nomic interdependence as measured by the ratio of bilateral trade to gross domestic product fell after World War I but rose again in subse- quent years.Most clear is the growth in the number of IGOs,though those associated with the creation and sustenance of a truly global economy largely emerge only after World War II.These trends for the 1885-1992 period are shown in Figure 1.16 Higher levels of democracy, interdependence,and IGO membership should,of course,reduce con- flict for the pairs of countries affected;but we also expect that as the number of democracies increases,trade grows,and IGOs proliferate, there will be important systemic influences on other pairs of states as well.The effect of the Kantian influences should,we hypothesize,be apparent over time as well as cross-nationally. their self-interest,see Daniel Lerner,"French Business Leaders Look at EDC,"Public Opinion Quarterly 24,no.1(1956);and Bruce Russett,Community and Contention:Britain and America in the Twentieth Century (Cambridge:MIT Press,1963),chap.9. 12 Robert O.Keohane and Lisa Martin,"The Promise of Institutionalist Theory,"International Se- curity 20,no.1(1995);Lisa Martin and Beth Simmons,"Theories and Empirical Studies of Interna- tional Institutions,"International Organization 52,no.4(1998). 13 For a review of some relevant hypotheses and findings,see Russett,Oneal,and Davis(fn.6). 14 Jaggers and Gurr (fn.2). is Samuel P.Huntington,The Third Wave:Democratization in the Late Twentieth Century (Norman: University of Oklahoma Press,1991). For graphing purposes the scale for bilateral trade/GDP has been increased by twoorders of mag- nitude and that for IGO membership has been reduced by one order of magnitude
6 WORLD POLITICS Even realists acknowledge that international institutions like NATO help to preserve peace among their members by supplementing the de terrent effect of sheer military power. Liberals emphasize the potential of institutions for communicating information and facilitating bargain ing,12 while constructivists see institutions as instruments for expand ing people's conceptions of identity, relatedness, and self-interest. Because IGOs vary widely in their functions and capabilities, any or all of these explanations may be correct in a particular instance.13 As with the consequences of democratic institutions, we do not attempt to re solve these theoretical debates here. Instead we seek to offer an empir ical assessment of the effect of the Kantian influences on interstate relations. In expanding the historical domain of the Kantian peace, one en counters hurdles (and opportunities) that arise from marked changes in the nature of political regimes, the importance of international trade, and the role of international organizations. As measured by the stan dard data on political regimes, Polity III,14 the average level of democ racy in the international system has risen since the early 1800s, in a pattern that is sporadic and wavelike.15 Similarly, the mean level of eco nomic interdependence as measured by the ratio of bilateral trade to gross domestic product fell after World War I but rose again in subse quent years. Most clear is the growth in the number of IGOs, though those associated with the creation and sustenance of a truly global economy largely emerge only after World War II. These trends for the 1885-1992 period are shown in Figure l.16 Higher levels of democracy, interdependence, and IGO membership should, of course, reduce con flict for the pairs of countries affected; but we also expect that as the number of democracies increases, trade grows, and IGOs proliferate, there will be important systemic influences on other pairs of states as well. The effect of the Kantian influences should, we hypothesize, be apparent over time as well as cross-nationally. their self-interest, see Daniel Lerner, "French Business Leaders Look at EDC," Public Opinion Quarterly 24, no. 1 (1956); and Bruce Russett, Community and Contention: Britain and America in the Twentieth Century (Cambridge: MIT Press, 1963), chap. 9. 12 Robert O. Keohane and Lisa Martin, "The Promise of Institutionalist Theory," International Se curity 20, no. 1 (1995); Lisa Martin and Beth Simmons, "Theories and Empirical Studies of Interna tional Institutions," International Organization 52, no. 4 (1998). 13 For a review of some relevant hypotheses and findings, see Russett, Oneal, and Davis (fn. 6). 14 Jaggers and Gurr (fn. 2). 15 Samuel P. Huntington, The Third Wave: Democratization in the Late Twentieth Century (Norman: University of Oklahoma Press, 1991). 16 For graphing purposes the scale for bilateral trade/GDP has been increased by two orders of mag nitude and that for IGO membership has been reduced by one order of magnitude
KANTIAN PEACE 7 ---AVGDEM·-AVGDEP—AVGIGO 15 C. 05 Year FIGURE 1 KANTIAN VARIABLES Our statistical method-pooled cross-sectional time-series regres- sion analysis of data regarding pairs of states(dyads)observed annually -is well suited to the purposes at hand.It considers variance in states' involvement in militarized disputes across dyads in each year and in dyadic relations through time.Consequently we can determine the likelihood of conflict as a function of differences across thousands of pairs of states annually and of changes in dyadic relations or in the in- ternational system from year to year over a period of more than one hundred years.By measuring change in the Kantian variables through time,we can begin to disentangle their systemic effects from their strictly dyadic influences. Changes over time in the average level of democracy,interdepen- dence,and IGO involvement capture important elements of the norms and institutions of the international system.Wendt,for instance,con- tends that world politics has slowly evolved from Hobbesian anarchy to a Lockean system wherein the security dilemma is ameliorated by norms recognizing the right of sovereign states to exist;these,in turn
KANTIAN PEACE 7 -AVGDEM.AVGDEP-AVGIGO | Year Figure 1 Kantian Variables Our statistical method?pooled cross-sectional time-series regres sion analysis of data regarding pairs of states (dyads) observed annually ?is well suited to the purposes at hand. It considers variance in states' involvement in militarized disputes across dyads in each year and in dyadic relations through time. Consequently we can determine the likelihood of conflict as a function of differences across thousands of pairs of states annually and of changes in dyadic relations or in the in ternational system from year to year over a period of more than one hundred years. By measuring change in the Kantian variables through time, we can begin to disentangle their systemic effects from their strictly dyadic influences. Changes over time in the average level of democracy, interdepen dence, and IGO involvement capture important elements of the norms and institutions of the international system. Wendt, for instance, con tends that world politics has slowly evolved from Hobbesian anarchy to a Lockean system wherein the security dilemma is ameliorated by norms recognizing the right of sovereign states to exist; these, in turn
8 WORLD POLITICS effectively limit the use of force.17 Thus,states are no longer subject to elimination:whereas twenty-two internationally recognized states were forcibly occupied or absorbed during the first half of the twentieth cen- tury,no state has lost its formal sovereignty through conquest since World War II.18 The emergence of a Kantian subsystem of states, within which the unprovoked use of force is illegitimate,may have con- tributed directly to this evolutionary development and affected the probability that force will be used primarily by states that are not par- ticularly democratic,interdependent,or involved in international orga- nizations. If democracies are more likely than are autocracies to win their wars, then the latter will have to be concerned about the security implications of weakening themselves in war,whether with democracies or other au- tocracies,especially as the number of democracies in the international system grows.19 If most great powers are democratic,their peaceful re- lations should reduce the incentive for war for all states across their spheres of influence.If globalization increases and stimulates economic growth among interdependent states,nonliberal states will have to be concerned lest they be punished by global markets and trading states for instigating international violence that disrupts trade and invest- ment;even antagonistic dyads with little mutual trade may find it pru- dent to avoid conflict.20 If international norms and institutions for 17 Wendt(fn.11).On some systemic effects of a high proportion of democracies,see Huntley (fn. 6);Nils Petter Gleditsch and Havard Hegre,"Peace and Democracy:Three Levels of Analysis,"Jour- nal of Confict Resolution 41,no.2(1997);Sara McLaughlin Mitchell,Scott Gates,and Havard Hegre, "Evolution in Democracy-War Dynamics,"Journal of Confict Resolution 43,no.6(1999);and Lars- Erik Cederman,"Back to Kant:Reinterpreting the Democratic Peace as a Collective Learning Pro- cess"(Manuscript,Political Science Department,University of California at Los Angeles,December 1998). iFor dates of independence,see Bruce Russett,J.David Singer,and Melvin Small,"National Po- litical Units in the Twentieth Century:A Standardized List,"American Political Science Review 62,no. 3(1968).Germany and Japan temporarily lost sovereignty after World War II,but soon regained it (Germany as two states).Kuwait was briefly occupied in 1990-91;but a large,diverse coalition of states under the aegis of the United Nations forced Iraq to withdraw in order to protect the sovereignty of established states.South Vietnam is an exception to this generalization if one regards its unification with North Vietnam in 1976 as the result of external conquest rather than of an internationalized civil war.Whereas state extinction as a consequence of international war has become rare,the ideology of ethnic self-determination has led to the breakup of many states and empires. 1 A counterhypothesis would be that as democracies become more numerous and more confident in their individual and collective strength,they may become emboldened to pursue coercive relationships with those autocracies that remain.For evidence that democracies do win most of their wars,see Bruce Bueno de Mesquita,Randolph Siverson,and Gary Woller,"War and the Fate of Regimes:A Com- parative Analysis,"American Political Science Review 86,no.3(1992);Lake (fn.7);and Allan C.Stam III,Win Lose or Draw (Ann Arbor:University of Michigan Press,1996). 20Thomas L.Friedman,The Lexus and the Olive Tree (New York:Farrar,Straus,and Giroux,1999); and Stephen G.Brooks,"The Globalization of Production and International Security"(Ph.D.diss., Yale University,forthcoming)
8 WORLD POLITICS effectively limit the use of force.17 Thus, states are no longer subject to elimination: whereas twenty-two internationally recognized states were forcibly occupied or absorbed during the first half of the twentieth cen tury, no state has lost its formal sovereignty through conquest since World War II.18 The emergence of a Kantian subsystem of states, within which the unprovoked use of force is illegitimate, may have con tributed directly to this evolutionary development and affected the probability that force will be used primarily by states that are not par ticularly democratic, interdependent, or involved in international orga nizations. If democracies are more likely than are autocracies to win their wars, then the latter will have to be concerned about the security implications of weakening themselves in war, whether with democracies or other au tocracies, especially as the number of democracies in the international system grows.19 If most great powers are democratic, their peaceful re lations should reduce the incentive for war for all states across their spheres of influence. If globalization increases and stimulates economic growth among interdependent states, nonliberal states will have to be concerned lest they be punished by global markets and trading states for instigating international violence that disrupts trade and invest ment; even antagonistic dyads with little mutual trade may find it pru dent to avoid conflict.20 If international norms and institutions for 17 Wendt (fn. 11). On some systemic effects of a high proportion of democracies, see Hundey (fn. 6); Nils Petter Gleditsch and Havard Hegre, "Peace and Democracy: Three Levels of Analysis," four nal of Conflict Resolution 41, no. 2 (1997); Sara McLaughlin Mitchell, Scott Gates, and Havard Hegre, "Evolution in Democracy-War Dynamics," fournal of Conflict Resolution 43, no. 6 (1999); and Lars Erik Cederman, "Back to Kant: Reinterpreting the Democratic Peace as a Collective Learning Pro cess" (Manuscript, Political Science Department, University of California at Los Angeles, December 1998). 18 For dates of independence, see Bruce Russett, J. David Singer, and Melvin Small, "National Po litical Units in the Twentieth Century: A Standardized List," American Political Science Review 62, no. 3 (1968). Germany and Japan temporarily lost sovereignty after World War II, but soon regained it (Germany as two states). Kuwait was briefly occupied in 1990-91; but a large, diverse coalition of states under the aegis of the United Nations forced Iraq to withdraw in order to protect the sovereignty of established states. South Vietnam is an exception to this generalization if one regards its unification with North Vietnam in 1976 as the result of external conquest rather than of an internationalized civil war. Whereas state extinction as a consequence of international war has become rare, the ideology of ethnic self-determination has led to the breakup of many states and empires. 19 A counterhypothesis would be that as democracies become more numerous and more confident in their individual and collective strength, they may become emboldened to pursue coercive relationships with those autocracies that remain. For evidence that democracies do win most of their wars, see Bruce Bueno de Mesquita, Randolph Siverson, and Gary Woller, "War and the Fate of Regimes: A Com parative Analysis," American Political Science Review 86, no. 3 (1992); Lake (fn. 7); and Allan C. Stam III, Win Lose or Draw (Ann Arbor: University of Michigan Press, 1996). 20 Thomas L. Friedman, TheLexus and the Olive Tree (New York: Farrar, Straus, and Giroux, 1999); and Stephen G. Brooks, "The Globalization of Production and International Security" (Ph.D. diss., Yale University, forthcoming)
KANTIAN PEACE 9 resolving disputes grow,even nonliberal states may be impelled to use regional or international organizations to help settle their disputes rather than accept the political,military,and economic costs imposed by the liberal community as penalties for using military force.Thus in- creases in the Kantian influences at the system level may have beneficial effects on the behavior of dyads that are not particularly democratic, economically interdependent,or involved in international organizations. This is not an ecological fallacy.21 We do not make inferences about dyadic conflict from information about conflict at the systemic level.In all our analyses we address the incidence of militarized disputes among pairs of states.We investigate the consequences of purely dyadic char- acteristics for dyadic behavior,but we also do consider the effects of evolutionary changes in the international system.To capture the effects of such systemic changes,we use the annual mean scores of democracy, bilateral trade as a proportion of gross domestic product(GDP),and joint memberships in IGOs graphed in Figure 1.They effectively gauge the pervasiveness of changes in international norms and institutions and document the example of the success of liberal states in the com- petition among nations.We also consider the influence of the leading state,the hegemon,on interstate relations.We investigate this aspect of leading realist theories with measures of the relative power of the hege- mon,states'satisfaction with the status quo,and the hegemon's sense of its own security. HISTORICAL DOMAIN,KEY VARIABLES,AND SOURCES OF DATA As our analysis spans the years 1885 to 1992,it enables us to examine the effects of democracy,economic interdependence,and international organizations over a long period before the cold war and for a few years after.Realists often contrast the dynamics of bipolar and multipolar systems,though there is disagreement over their consequences for in- terstate relations.By Waltz's criteria,the international system was mul- tipolar for the centuries preceding 1945 but bipolar during the cold war.22 And the current,post-Soviet world is neither bipolar nor multi- polar but perhaps is best understood as unipolar,at least as measured by 2 Identified by W.S.Robinson,"Ecological Correlations and the Behavior of Individuals,"Ameri- can Sociological Review 15,no.3(1950).On how some inferences can be made,see Gary King,A Solu- tion to the Ecological Inference Problem(Princeton:Princeton University Press,1997). 22 Kenneth Waltz says that it is the power of the units(states)themselves that defines polarity and not the number or power of the alliances they lead;see Waltz,Theory of International Politics(Reading, Mass.:Addison-Wesley,1979),98-99.Thus the formation of two opposing alliance systems prior to World War I did not change the structure of the multipolar system.Waltz's emphasis on the systemic
KANTIAN PEACE 9 resolving disputes grow, even nonliberal states may be impelled to use regional or international organizations to help settle their disputes rather than accept the political, military, and economic costs imposed by the liberal community as penalties for using military force. Thus in creases in the Kantian influences at the system level may have beneficial effects on the behavior of dyads that are not particularly democratic, economically interdependent, or involved in international organizations. This is not an ecological fallacy.21 We do not make inferences about dyadic conflict from information about conflict at the systemic level. In all our analyses we address the incidence of militarized disputes among pairs of states. We investigate the consequences of purely dyadic char acteristics for dyadic behavior, but we also do consider the effects of evolutionary changes in the international system. To capture the effects of such systemic changes, we use the annual mean scores of democracy, bilateral trade as a proportion of gross domestic product (GDP), and joint memberships in IGOs graphed in Figure 1. They effectively gauge the pervasiveness of changes in international norms and institutions and document the example of the success of liberal states in the com petition among nations. We also consider the influence of the leading state, the hegemon, on interstate relations. We investigate this aspect of leading realist theories with measures of the relative power of the hege mon, states' satisfaction with the status quo, and the hegemon's sense of its own security. Historical Domain, Key Variables, and Sources of Data As our analysis spans the years 1885 to 1992, it enables us to examine the effects of democracy, economic interdependence, and international organizations over a long period before the cold war and for a few years after. Realists often contrast the dynamics of bipolar and multipolar systems, though there is disagreement over their consequences for in terstate relations. By Waltz's criteria, the international system was mul tipolar for the centuries preceding 1945 but bipolar during the cold war.22 And the current, post-Soviet world is neither bipolar nor multi polar but perhaps is best understood as unipolar, at least as measured by 21 Identified by W. S. Robinson, "Ecological Correlations and the Behavior of Individuals, "Ameri can Sociological Review 15, no. 3 (1950). On how some inferences can be made, see Gary King, A Solu tion to the Ecological Inference Problem (Princeton: Princeton University Press, 1997). 22 Kenneth Waltz says that it is the power of the units (states) themselves that defines polarity and not the number or power of the alliances they lead; see Waltz, Theory of International Politics (Reading, Mass.: Addison-Wesley, 1979), 98-99. Thus the formation of two opposing alliance systems prior to World War I did not change the structure of the multipolar system. Waltz's emphasis on the systemic
