Existing research has demonstrated that the ability of secessionist movements to mobilize is highly contingent on assistance from external actors, especially via transborder ethnic ties. The specific relationship between kin state and kin group is seen as particularly enhancing the opportunities for secessionism/irredentism. Yet the analysis of data (1989-2011) does not support this claim. Relatively few groups with kin states have engaged in violent secessionism, and these examples are mostly restricted to successor states from Yugoslavia and the Soviet Union. Thus, this article argues there are a number of reasons why the relationship between kin state and group increasingly engenders moderation. These are: the failure of irredentism as a policy and idea; the asymmetric and problematic relations between kin state and group; and the protective capacity and the provision of resources by the kin state. As such, while external help is vital for secessionist groups to successfully mobilize, kin states typically provide assistance that fosters restraint and peace among their kin.