Target state responses to external support of rebel groups: Revealing the impact of support level and interstate strategic interaction

How do target states react to third-party sponsorship of rebel groups? In this article, we provide a typology of responses from target states based on their severity and comprehensiveness level. We argue that the external support level and existing strategic interaction between targets and sponsors are crucial to explain the variation in target responses toward state sponsors since they affect the target states’ level of perceived threat. We test our theoretical claims using an original dataset featuring target responses between 1991 and 2010. Our findings show that strategic rivalry is the most crucial factor in increasing the severity and comprehensiveness of responses. Higher levels of support for rebel groups increase only coercive responses and do not impact comprehensiveness, whereas formal alliances decrease the adoption of mixed responses. Our study contributes to the literature on the external support of rebels and conflict management with implications for predicting target states’ responses to sponsorship.