Abstract

Collective action is volatile: characterized by swift, unexpected changes in intensity, target, and forms. We conduct a detailed exploration of four reasons that these changes occur. First, action is about identities which are fluid, contested, and multifaceted. As the content of groups' identities change, so do the specific norms for the identities. Second, social movements adopt new tactics, or forms of collective action. Tactical changes may arise from changes in identity, but also changes in the target or opponent groups, and changes in the relationships with targets and with other actors. Factions or wings of a group in conflict may in turn form identities based on opposition or support for differing tactics. Third, social movements change because participant motivation ebbs, surges, and also changes in quality. Finally, political social change occurs within socio-political structures; these structures implicate higher-level norms, which both constrain and emerge from actions. Our analysis presents idealized and descriptive models of these relationships, and a new model to examine tactical changes empirically, the DIME model. This model highlights that collective actors canDisidentify after failure ; they canInnovate, or try something new; and they can commit harder, convinced that they are right, with increased moral urgency and redoubled efforts.