Competition from Within: Ethnicity, Power, and Militant Group Rivalry

Why do militant groups turn on each other? This behavior is somewhat puzzling, since such groups are often on the same side of a conflict. A growing body of literature seeks to understand political violence by looking at cooperative and competitive relationships among non-state actors. Debates continue about the sources of militant group rivalry. We argue that shared motivations, especially ethnic motivations, along with power differences among groups should help explain inter-group fighting. Our analysis uses new dyadic data on rivalry among the militant groups of Africa and Asia since 1990. Unlike some previous studies, we analyze both terrorist and insurgent organizations. Results suggest that pairs of groups with a shared ethnic identity are more likely than others to have rivalrous relationships. Power asymmetry is also somewhat associated with rivalry, but interaction models indicate that the association is only statistically significant in the presence of shared ethnic motivations.