Over the past decade, the study of political violence and radicalization has moved from theoretical frameworks and case studies towards large-scale observational studies focusing on factors such as negative life experiences, loss of significance and grievances that are correlated with supporting political violence and perceiving intergroup relations to be mainly hostile. This paper argues that since frameworks for how people come to engage in political violence talk about cause and effect, experimental studies offer a venue for future research. The paper reports the results of a large population representative concurrent double randomization design study (n=3000) in the US and Denmark. The experiment manipulated feelings of personal uncertainty and “dark mindset”, the experience that the world is a vile place where deliberation is futile, and measured support for and intentions to engage in acts of political violence in defence of one’s political group. The results indicate that feelings of personal uncertainty increase intentions to engage in political violence in defence of their group through the adoption of a dark mindset. The results illuminate a central causal pathway in radicalisation to political violence and shows the utility of experimental research in the study of political violence and violent conflict.
