Published online by Cambridge University Press: 22 May 2009
Realist and other scholars commonly hold that rationally led states can and sometimes do fight when no peaceful bargains exist that both would prefer to war. Against this view, I show that under very broad conditions there will exist negotiated settlements that genuinely rational states would mutually prefer to a risky and costly fight. Popular rationalist and realist explanations for war fail either to address or to explain adequately what would prevent leaders from locating a less costly bargain. Essentially just two mechanisms can resolve this puzzle on strictly rationalist terms. The first turns on the fact that states have both private information about capabilities and resolve and the incentive to misrepresent it. The second turns on the fact that in specific strategic contexts states may be unable credibly to commit to uphold a mutually preferable bargain. Historical examples suggest that both mechanisms are empirically plausible.
An earlier version of this article was presented at the annual meetings of the American Political Science Association, Washington, D.C., 2–5 September 1993. The article draws in part on chapter 1 of James D. Fearon, “Threats to Use Force: Costly Signals and Bargaining in International Crises,” Ph.D. diss., University of California, Berkeley, 1992. Financial support of the Institute on Global Conflict and Cooperation of the University of California is gratefully acknowledged. For valuable comments I thank Eddie Dekel, Eric Gartzke, Atsushi Ishida, Andrew Kydd, David Laitin, Andrew Moravcsik, James Morrow, Randolph Siverson, Daniel Verdier, Stephen Walt and especially Charles Glaser and Jack Levy.
1. Of course, arguments of the second sort may and often do presume rational behavior by individual leaders; that is, war may be rational for civilian or military leaders if they will enjoy various benefits of war without suffering costs imposed on the population.While I believe that “second-image” mechanisms of this sort are very important empirically, I do not explore them here. A more accurate label for the subject of the article might be “rational unitary-actor explanations,” but this is cumbersome.
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31. See Claim 2 in the Appendix.
32. For examples and discussion on this point, see Fearon, “Threats to Use Force,” chap. 3.
33. See the Appendix for proofs of these claims. Cheap talk announcements can affect outcomes in some bargaining contexts. For an example from economics, see Farrell, Joseph and Gibbons, Robert, “Cheap Talk Can Matter in Bargaining,” Journal of Economic Theory 48 (06 1989), pp. 221–37CrossRefGoogle Scholar. These authors show how cheap talk might credibly signal a willingness to negotiate seriously that then affects subsequent terms of trade. For an example from international relations, see Morrow, James D., “Modeling the Forms of International Cooperation: Distribution Versus Information,” International Organization 48 (Summer 1994), pp. 387–423CrossRefGoogle Scholar.
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71. The assumption that type cB=x - p chooses not to fight is immaterial.