The Comedy of Errors? A Reply to Mette Eilstrup-Sangiovanni

In her response to our article, Mette Eilstrup-Sangiovanni replaces balance-of-power theory (threat of hegemony begets balancing, which produces a tendency of international systems toward equilibria of power) with a complex congeries of competing and contingent conjectures about when states might balance. While these are certainly part of the extensive literature on the balance of power, lumping them together and calling them a `theory' invites a comedy of errors rather than an empirical test. The `ado' in our article was a novel empirical test of a theory that has been central to centuries of IR theorizing. As our review of the evidence confirms, this theory can indeed be evaluated in ancient and non-European international systems, and it is wrong: international systems do not tend toward equilibria of power, and balancing is relatively unimportant in explaining the equilibria that do occur. We end up agreeing with the gist of Sangiovanni's response: there is no empirically valid systemic balance-of-power theory, and it is time to turn to contingent middle-range hypotheses about balancing behavior.