Militia groups—once associated primarily with conflict zones—have become increasingly visible in stable democracies, challenging prevailing theories of political violence. Yet systematic evidence on why citizens support them remains limited. This study addresses that gap using original survey experiments fielded in Czechia, Slovakia, Poland, and Hungary to identify the institutional, structural, and attitudinal foundations of militia support. We find that support for militias is not driven by economic deprivation, ideological extremism, rurality, or masculinity—factors emphasized in existing accounts. Instead, citizens support militias as a strategic response to perceived failures of governance, sovereignty enforcement, and cultural protection. These logics, however, vary by state context. In Czechia and Slovakia, where the state is widely viewed as weak in addressing political grievances and defending cultural boundaries, militias function as substitutes for state authority and mobilize around political grievances, exclusionary nationalism, and boundary enforcement. In Poland and Hungary, where nationalist governments actively police cultural and territorial boundaries, militias operate as co-enforcers rather than challengers of the state. Finally, we argue that state responses—repression, tolerance, and co-optation—shape both support for militias and their long-term viability. Repression can entrench militia movements by casting them as legitimate resistance forces, whereas co-optation reduces their independence and public appeal. Taken together, these findings challenge economic and ideological determinist models and demonstrate that support for militias in democracies is best understood as a strategic response to state legitimacy crises and perceived failures of cultural and political boundary enforcement. *part of organized panel, Dr. Jesse Hronesova (UCL)