Theory, Data, and Deterrence: A Response to Kenwick, Vasquez, and Powers

Abstract

Kenwick, Vasquez, and Powers question whether empirical evidence supports the claim that defense pacts deter conflict as our prior research has concluded. We review the theoretical argument for why defense pacts should deter conflict and consider the challenges inherent in evaluating deterrence using observational data. We then consider whether the research design choices of Kenwick et al. improve upon our research design. We demonstrate that claims that defense pacts deter conflict are robust to many of these changes in research design, and we argue that the consequential difference, while perhaps appropriate for testing the Steps-to-War argument, is not appropriate for testing the deterrent effect of defense pacts. We conclude by noting that a deterrence effect of defense pacts is not necessarily incompatible with aspects of the Steps-to-War argument, and we suggest profitable new directions for testing the Steps-to-War approach.