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The Bar Fight Theory of International Conflict: Regime Type, Coalition Size, and Victory*


Studies of regime type and war show that democracies tend to win the wars they fight, but questions remain about why this is the case. A simple, if underappreciated, explanation for democratic success is that democracies fight alongside larger and more powerful coalitions. Coalition partners bring additional material capabilities and may also provide intangible benefits to the war effort, such as increased legitimacy or confidence. Democracies may also find it less costly to join coalitions, as democratic war aims may be easier to apportion among the victors without diluting the spoils. Evaluating our hypotheses in a sample of all wars (or all militarized disputes) during the period 1816–2000, we find that democracies fight alongside larger coalitions and that states fighting alongside larger coalitions are more likely to win major contests. Coalition size subsumes most (and in some specifications all) of the direct effect of regime type on victory.

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Benjamin A. T. Graham is an Assistant Professor in the Department of Political Science, University of Southern California, 3518 Trousdale Pkwy Von KleinSmid Center 330, Los Angeles, CA 90089-0043 ( Erik Gartzke is a Professor in the Department of Political Science, University of California, San Diego 9500 Gilman Drive/Office 327 SSB, 0521 La Jolla, CA 92093-0521 ( Christopher J. Fariss is a Jeffrey L. Hyde and Sharon D. Hyde and Political Science Board of Visitors Early Career, Professor in Political Science and Assistant Professor in the Department of Political Science, Pennsylvania State University, 200 Pond Lab, University Park, PA 16802 ( The authors would like to thank the participants of the 2011 meeting of the International Studies Association and the 2010 meeting of the International Studies Association West. To view supplementary material for this article, please visit

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