(A)moral underpinnings of militant extremist thinking pattern: The role of moral foundations and Dark Tetrad

We investigated the association between the Militant Extremist Mindset (MEM)—a measure of radicalisation consisting of Proviolence (advocating ideological violence), Vile World (pessimistic worldview) and Divine Power (excusing violence on divine grounds)—and dark traits as (a)moral personal dispositions and moral foundations as a moral reasoning framework. In Study 1 ( N = 309), low individualising foundations (care, fairness) predicted Proviolence and Divine Power. High binding foundations (loyalty, authority, purity) predicted Divine Power and the Vile World. In Study 2 ( N = 540), binding foundations positively predicted all MEM components. Individualising foundations negatively predicted Proviolence and Divine Power, but positively predicted the Vile World. Dark traits predicted MEM directly and via moral foundations. Sadism was the most important for understanding Proviolence and Divine Power (via low individualising foundations), while Machiavellianism predicted the Vile World (via high binding foundations). Our study confirms the importance of dark traits in understanding radicalisation and highlights that endorsing and excusing ideological violence is linked to a disregard for individual wellbeing (associated with sadistic tendencies), and to an endorsement of group-level morality (associated with a tendency for strategic manipulation). The heterogeneity of the Vile World in terms of moral thinking frameworks should be explored in further studies. • Justifying violence linked to low care/fairness and high loyalty/authority/purity. • Vile World belief relates positively to both individual- and group-focused morals. • Dark traits predict MEM components directly and via moral foundations. • Sadism is most important for understanding violent aspects of MEM.