ABSTRACTScholarship explores the impact of human rights abuse and state repression on terrorism. Heretofore, scholarship has ignored the impact of government-sponsored killings on domestic terrorism. This article proposes that mass killings create a focal point for terrorist mobilization. The vendetta agenda fuels violence by animating retributory violence. Additionally, mass atrocities create a permissive environment for violent nonstate activity. A spiral of violence ensues whereby groups resort to terrorism. Utilizing data from the Global Terrorism Database, 1971–2011, the study shows that mass killings significantly increase domestic terrorism. It contributes to emerging scholarship examining how state policies influence terrorist activity.