Contextual Tripwire Effects? Exploring Public and Elite Reactions to Attacks

• In Event: Forward Deployment, Coercive Diplomacy, and Conflict

Abstract

Scholars and practitioners have long invoked tripwire deployments as bolstering the credibility of extended deterrence pledges. By situating even small number of troops in harm’s way, the logic goes, a country can make more credible its pledge to intervene in even a costly conflict. Should a country’s own troops come under attack, the pressures to intervene would be much greater than if its troops were not present. Such “tripwire” or “plate-glass” deployments have been particularly important to justifications for U.S. guarantees in Europe and elsewhere since the Cold War. Yet the validity of mechanisms by which such pressures would be generated have been largely assumed, not established. We test the most commonly adduced and strongest tripwire logics using survey experiments of U.S. public and elites. Because such mechanisms often informally invoke concerns about reputation to explain the putative strength of tripwire effects, stronger tests of tripwire logics should take place when such considerations are nearer the fore. Accordingly, we include tests of tripwire effect strength conducted immediately before and after Russia’s invasion of Ukraine and during a crisis when it appeared that Russian missiles might have struck NATO member Poland, in addition to experiments conducted during non-crisis periods. Our findings tentatively suggest that tripwire logics are neither as strong nor as automatic as widely assumed.

Authors

• Paul Musgrave, University of Massachusetts

• Steven Ward, University of Cambridge