Re-Evaluating Capitalist and Democratic Peace Models


  • Author’s notes: For constructive and helpful comments, I wish to thank Allan Dafoe, Patricia Hajek, Shali Luo, John Oneal, Matthew Powers, Bruce Russett, George Tsebelis, and Bennet Zelner. Replication materials are available on the Dataverse Network Project at


After replicating Oneal and Russett’s (International Studies Quarterly, 41, 1997, 267; Journal of Peace Research, 36, 1999, 423) democratic peace model, Gartzke’s (American Journal of Political Science, 51, 2007, 180) study contends that “capitalism, and not democracy, leads to peace. Additional research is needed to corroborate, extend, and even refute the findings reported here.” In response to this open invitation, this study re-evaluates Gartzke’s capitalist peace model along with Oneal and Russett’s democratic peace model. This study identifies that while the capitalist peace model suffers from model misspecification, observation omission, and sample selection bias, the democratic peace model commits measurement error. After correcting these four problems, this study uncovers that while capitalism does not emerge as a cause mitigating militarized disputes or wars in a consistent manner, democracy does.