Are leaders from certain parties particularly likely to engage in military conflict? This question is difficult to answer because of selection bias. For example, countries may be more likely to elect right-wing leaders if their publics are more hawkish or if the international system is particularly dangerous. Put simply, who comes to power is not random, which makes causal inference difficult. We overcome this problem by using a regression discontinuity design. Specifically, we look at close presidential elections that were essentially “tossups” between two candidates. We find that electing right-wing candidates increases state aggression. We also find that electing candidates from challenger parties makes countries much more likely to initiate military disputes, particularly in the first year of the new leader’s term. This result is consistent with other studies that find that the likelihood of state aggression increases following major leadership transitions.

References

Arena, Philip, Palmer, Glenn. 2009 . “ Politics or the Economy? Domestic Correlates of Dispute Involvement in Developed Democracies .” International Studies Quarterly 53 (4): 955 – 75 .

Google Scholar Crossref | ISI

Beland, Louis-Philippe . 2015 . “ Political Parties and Labor-market Outcomes: Evidence from US States .” American Economic Journal: Applied Economics 7 (4): 198 – 220 .

Google Scholar Crossref

Bertoli, Andrew D. 2017 . “ Nationalism and Conflict: Lessons from International Sports .” International Studies Quarterly 61 (4): 835 – 49 .

Google Scholar Crossref

Bertoli, Andrew D., Dafoe, Allan, Trager, Robert. 2018 . “ The Young and the Reckless: Leader Age and International Conflict .” Working Paper. https://www.dropbox.com/s/ktctr5gnjfv6gp7/Age_Online_Appendix.pdf?dl=0.

Google Scholar

Boer, Diana, Fischer, Ronald. 2013 . “ How and When Do Personal Values Guide Our Attitudes and Sociality? Explaining Cross-cultural Variability in Attitude-value Linkages .” Psychological Bulletin 139 (5): 1113 – 147 .

Google Scholar Crossref | Medline

Byman, Daniel, Pollack, Kenneth. 2001 . “ Let Us Now Praise Great Men: Bringing the Statesman Back In .” International Security 25 (4): 107 – 46 .

Google Scholar Crossref | ISI

Calonico, Sebastian, Cattaneo, Matias D., Titiunik, Rocio. 2014 . “ Robust Nonparametric Confidence Intervals for Regression-discontinuity Designs .” Econometrica 82 (6): 2295 – 326 .

Google Scholar Crossref | ISI

Cattaneo, Matias D., Frandsen, Brigham R., Titiunik, Rocio. 2015 . “ Randomization Inference in the Regression Discontinuity Design: An Application to Party Advantages in the US Senate .” Journal of Causal Inference 3 (1): 1 – 24 .

Google Scholar Crossref

Caughey, Devin, Sekhon, Jasjeet S.. 2011 . “ Elections and the Regression Discontinuity Design: Lessons from Close US House Races, 1942–2008 .” Political Analysis 19 (4): 385 – 408 .

Google Scholar Crossref | ISI

Chiozza, Giacomo, Goemans, Hein E.. 2011 . Leaders and International Conflict. New York : Cambridge University Press .

Google Scholar Crossref

Clare, Joe . 2010 . “ Ideological Fractionalization and the International Conflict Behavior of Parliamentary Democracies .” International Studies Quarterly 54 (4): 965 – 87 .

Google Scholar Crossref | ISI

Clarke, Kevin A. 2005 . “ The Phantom Menace: Omitted Variable Bias in Econometric Research .” Conflict Management and Peace Science 22 (4): 341 – 52 .

Google Scholar SAGE Journals | ISI

Colgan, Jeff D. 2010 . “ Oil and Revolutionary Governments: Fuel for International Conflict .” International Organization 64 (4): 661 – 94 .

Google Scholar Crossref | ISI

Croco, Sarah E. 2015 . Peace at What Price? New York : Cambridge University Press .

Google Scholar Crossref

Dafoe, Allan . 2011 . “ Statistical Critiques of the Democratic Peace: Caveat Emptor .” American Journal of Political Science 55 (2): 247 – 62 .

Google Scholar Crossref | ISI

Dafoe, Allan . 2012 . “ Resolve, Reputation, and War: Cultures of Honor and Leaders’ Time-in-office .” PhD thesis, University of California , Berkeley . Accessed July 30, 2017. http://www.allandafoe.com.

Google Scholar

Dafoe, Allan, Caughey, Devin. 2016 . “ Honor and War .” World Politics 68 (2): 341 – 81 .

Google Scholar Crossref | ISI

de Benedictis-Kessner, Justin, Warshaw, Christopher. 2016 . “ Mayoral Partisanship and Municipal Fiscal Policy .” Journal of Politics 78 (4): 1124 – 138 .

Google Scholar Crossref

Dunning, Thad . 2012 . Natural Experiments in the Social Sciences: A Design-based Approach. New York : Cambridge University Press .

Google Scholar Crossref

Eggers, Andrew C., Fowler, Anthony, Hainmueller, Jens, Hall, Andrew B., Snyder, James M.. 2015 . “ On the Validity of the Regression Discontinuity Design for Estimating Electoral Effects: New Evidence from over 40,000 Close Races .” American Journal of Political Science 59 (1): 259 – 74 .

Google Scholar Crossref

Eggers, Andrew C., Hainmueller, Jens. 2009 . “ MPs for Sale? Returns to Office in Postwar British Politics .” American Political Science Review 103 (4): 513 – 33 .

Google Scholar Crossref | ISI

Eundak, Kwon . 2006 . “ Perceptions toward North Korea’s Nuclear Weapons Program: Findings from a Public Opinion Survey .” East Asia 23 (4): 61 – 84 .

Google Scholar Crossref

Freedman, David A. 2009 . Statistical Models: Theory and Practice. New York : Cambridge University Press .

Google Scholar Crossref

Gelpi, Christopher, Grieco, Joseph M.. 2001 . “ Attracting Trouble: Democracy, Leadership Tenure, and the Targeting of Militarized Challenges, 1918–1992 .” Journal of Conflict Resolution 45 (6): 794 – 817 .

Google Scholar SAGE Journals | ISI

Gerber, Elisabeth R., Hopkins, Daniel J.. 2011 . “ When Mayors Matter: Estimating the Impact of Mayoral Partisanship on City Policy .” American Journal of Political Science 55 (2): 326 – 39 .

Google Scholar Crossref | ISI

Ghosn, Faten, Palmer, Glenn, Bremer, Stuart A.. 2004 . “ The MID3 Data Set, 1993–2001: Procedures, Coding Rules, and Description .” Conflict Management and Peace Science 21 (2): 133 – 54 .

Google Scholar SAGE Journals | ISI

Graham, Jesse, Haidt, Jonathan, Nosek, Brian A.. 2009 . “ Liberals and Conservatives Rely on Different Sets of Moral Foundations .” Journal of Personality and Social Psychology 96 (5): 1029 – 46 .

Google Scholar Crossref | Medline | ISI

Gries, Peter . 2014 . The Politics of American Foreign Policy: How Ideology Divides Liberals and Conservatives over Foreign Affairs. Stanford, CA : Stanford University Press .

Google Scholar

Haas, Mark L. 2005 . The Ideological Origins of Great Power Politics, 1789–1989. Ithaca, NY : Cornell University Press .

Google Scholar

Hickey, Donald R. 1989 . The War of 1812: A Forgotten Conflict. Chicago : University of Illinois Press .

Google Scholar

Horowitz, Michael C., Stam, Allan C., Ellis, Cali M.. 2015 . Why Leaders Fight. New York : Cambridge University Press .

Google Scholar Crossref

Jervis, Robert . 2003 . “ The Compulsive Empire .” Foreign Policy 137: 83 – 87 .

Google Scholar

Jones, Benjamin F., Olken, Benjamin A.. 2009 . “ Hit or Miss? The Effect of Assassinations on Institutions and War .” American Economic Journal: Macroeconomics 1 (2): 55 – 87 .

Google Scholar Crossref | ISI

Kertzer, Joshua D., Rathbun, Brian C.. 2015 . “ Fair Is Fair: Social Preferences and Reciprocity in International Politics .” World Politics 67 (4): 613 – 55 .

Google Scholar Crossref | ISI

Kertzer, Joshua D., Powers, Kathleen E., Rathbun, Brian C., Iyer, Ravi. 2014 . “ Moral Support: How Moral Values Shape Foreign Policy Attitudes .” The Journal of Politics 76 (3): 825 – 40 .

Google Scholar Crossref

Krause, Volker . 2004 . “ Hazardous Weapons? Effects of Arms Transfers and Defense Pacts on Militarized Disputes, 1950–1995 .” International Interactions 30 (4): 349 – 71 .

Google Scholar Crossref | ISI

Lee, David S. 2008 . “ Randomized Experiments from Non-random Selection in US House Elections .” Journal of Econometrics 142 (2): 675 – 97 .

Google Scholar Crossref | ISI

Lee, David S., Card, David. 2008 . “ Regression Discontinuity Inference with Specification Error .” Journal of Econometrics 142 (2): 655 – 74 .

Google Scholar Crossref | ISI

Leeds, Brett Ashley . 2003 . “ Do Alliances Deter Aggression? The Influence of Military Alliances on the Initiation of Militarized Interstate Disputes .” American Journal of Political Science 47 (3): 427 – 39 .

Google Scholar Crossref | ISI

Levy, Jack S., Mabe, William F.. 2004 . “ Politically Motivated Opposition to War .” International Studies Review 6 (4): 65 – 84 .

Google Scholar Crossref

Lieberfeld, Daniel . 2005 . “ Theories of Conflict and the Iraq War .” International Journal of Peace Studies. 10 (2): 1 – 21 .

Google Scholar

Mattes, Michaela, Leeds, Brett Ashley, Carroll, Royce. 2015 . “ Leadership Turnover and Foreign Policy Change: Societal Interests, Domestic Institutions, and Voting in the United Nations .” International Studies Quarterly 59 (2): 280 – 90 .

Google Scholar Crossref | ISI

Mattes, Michaela, Leeds, Brett Ashley, Matsumura, Naoko. 2016 . “ Measuring Change in Source of Leader Support: The CHISOLS Dataset .” Journal of Peace Research 53 (2): 259 – 67 .

Google Scholar SAGE Journals | ISI

Mearsheimer, John J. 2001 . The Tragedy of Great Power Politics. New York : University of Chicago Press .

Google Scholar

Mearsheimer, John J., Walt, Stephen M.. 2003 . “ Can Saddam Be Contained? History Says Yes .” Foreign Policy Bulletin 14 (1): 219 – 24 .

Google Scholar Crossref

Morgan, T. Clifton, Campbell, Sally Howard. 1991 . “ Domestic Structure, Decisional Constraints, and War: So Why Kant Democracies Fight? ” Journal of Conflict Resolution 35 (2): 187 – 211 .

Google Scholar SAGE Journals | ISI

Nosek, Brian A., Alter, G., Banks, G. C., Borsboom, D., Bowman, S. D., Breckler, S. J., Buck, S., Chambers, C. D., Chin, G., Christensen, G., Contestabile, M., Dafoe, A., Eich, E., Freese, J., Glennerster, R., Goroff, D., Green, D. P., Hesse, B., Humphreys, M., Ishiyama, J., Karlan, D., Kraut, A., Lupia, A., Mabry, P., Madon, T., Malhotra, N., Mayo-Wilson, E., McNutt, M., Miguel, E., Levy Paluck, E., Simonsohn, U., Soderberg, C., Spellman, B. A., Turitto, J., VandenBos, G., Vazire, S., Wagenmakers, E. J., Wilson, R., Yarkoni, T.. 2015 . “ Promoting an Open Research Culture .” Science 348 (6242): 1422 – 425 .

Google Scholar Crossref | Medline | ISI

Paletta, Damian . 2016 . “ Clinton vs. Trump: Where They Stand on Foreign Policy Issues .” Wall Street Journal. Accessed December 11, 2017. http://graphics.wsj.com/elections/2016/donald-trump-hillary-clinton-on-foreign-policy/.

Google Scholar

Palmer, Glenn, London, Tamar, Regan, Patrick. 2004 . “ What’s Stopping You?: The Sources of Political Constraints on International Conflict Behavior in Parliamentary Democracies .” International Interactions 30 (1): 1 – 24 .

Google Scholar Crossref | ISI

Pearl, Judea . 2013 . “ Linear Models: A Useful ‘Microscope’ for Causal Analysis .” Journal of Causal Inference 1 (1): 155 – 70 .

Google Scholar Crossref

Pettersson-Lidbom, Per . 2008 . “ Do Parties Matter for Economic Outcomes? A Regression-discontinuity Approach .” Journal of the European Economic Association 6 (5): 1037 – 56 .

Google Scholar Crossref | ISI

Potter, Philip B. K. 2007 . “ Does Experience Matter? American Presidential Experience, Age, and International Conflict .” Journal of Conflict Resolution 51 (3): 351 – 78 .

Google Scholar SAGE Journals | ISI

Rathbun, Brian C. 2004 . Partisan Interventions: European Party Politics and Peace Enforcement in the Balkans. Ithaca, NY : Cornell University Press .

Google Scholar Crossref

Saunders, Elizabeth N. 2011 . Leaders at War: How Presidents Shape Military Interventions. Ithaca, NY : Cornell University Press .

Google Scholar Crossref

Schultz, Kenneth A. 2005 . “ The Politics of Risking Peace: Do Hawks or Doves Deliver the Olive Branch? ” International Organization 59 (1): 1 – 38 .

Google Scholar Crossref | ISI

Schwartz, Shalom H. 1992 . “ Universals in the Content and Structure of Values: Theoretical Advances and Empirical Tests in 20 Countries .” Advances in Experimental Social Psychology 25 (1): 1 – 65 .

Google Scholar Crossref | ISI

Schwartz, Shalom H., Caprara, Gian Vittorio, Vecchione, Michele. 2010 . “ Basic Personal Values, Core Political Values, and Voting: A Longitudinal Analysis .” Political Psychology 31 (3): 421 – 52 .

Google Scholar Crossref | ISI

Solingen, Etel . 2009 . Nuclear Logics: Contrasting Paths in East Asia and the Middle East. Princeton, NJ : Princeton University Press .

Google Scholar Crossref

Stein, Rachel . 2015 . “ War and Revenge: Explaining Conflict Initiation by Democracies .” American Political Science Review 109 (3): 556 – 73 .

Google Scholar Crossref

Trager, Robert F . 2004 . “ Valence Politics in International Crises .” Unpublished Manuscript, Columbia University . Accessed April 16, 2018. http://www.roberttrager.com/Research_files/Valence2.pdf.

Google Scholar

Trager, Robert F., Vavreck, Lynn. 2011 . “ The Political Costs of Crisis Bargaining: Presidential Rhetoric and the Role of Party .” American Journal Political Science 55 (3): 526 – 45 .

Google Scholar Crossref | ISI

Voeten, Erik . 2014 . “ Does Participation in International Organizations Increase Cooperation? ” The Review of International Organizations 9 (3): 285 – 308 .

Google Scholar Crossref

Wolford, Scott . 2007 . “ The Turnover Trap: New Leaders, Reputation, and International Conflict .” American Journal of Political Science 51 (4): 772 – 88 .

Google Scholar Crossref | ISI

Women’s Health Initiative . 2002 . “ Risks and Benefits of Estrogen Plus Progestin in Healthy Postmenopausal Women: Principal Results from the Women’s Health Initiative Randomized Controlled Trial .” JAMA 288 (3): 321 – 33 .

Google Scholar Crossref | Medline