The Enforcement Problem in Coercive Bargaining: Interstate Conflict over Rebel Support in Civil Wars

This article explores the strategic problems that arise when a state seeks to use military force to compel changes in another state's policies. Although the costs associated with military action mean that there generally exist compromises that both sides prefer to conflict, bargaining may fail if such deals are not enforceable in the face of temptations to renege on policy concessions. This study develops a model that shows that inefficient conflict can occur when states bargain over policies that one of them can change unilaterally and covertly. I then show that this theory is useful for understanding a common source of international conflict: conflicts that arise when one state supports rebel groups engaged in a civil war with another state. Episodes of rebel support are associated with a substantial increase in the risk of interstate militarized disputes, the lethality of these disputes, and the likelihood of repeated violence. Agreements to limit rebel support are unlikely to reduce interstate violence unless they are coupled with concessions by the target state and/or monitoring mechanisms, both of which are shown theoretically to mitigate the enforcement problem.