Ordinary mechanisms, extraordinary actions: Explaining the universality and uniqueness of political violence

Political violence is widespread in potential but uneven in expression. I propose a two-level integrative framework that helps explain the capacity for and expression of political violence, derived from the broadening interdisciplinary behavioral science research on violence. The first level of this framework centers on species-typical psychological mechanisms (common across humans) that regulate coalitional dynamics such as moralization, identity categorization, and collection action for violence. The second level focuses on individual-level catalysts: person-specific variable traits that predispose some individuals to cross the threshold into violent action. While each perspective is supported by extensive research across the social sciences, political science has yet to synthesize them explicitly into a single coherent model. Integrating these two levels offers a comprehensive foundation for analyzing a broad spectrum of political violence, at once both reconciling and moving beyond fruitless nature-vs-nurture type stalemates to help explain both the ubiquity and variability of an ancient vice.