Objectives: This study examined three hypotheses concerning the association of armed political violence with moral judgment, critical thinking, and Islamic fundamentalism, and the contribution of each of them to violence. The study also assessed the possible differences in the means of the armed political violence between individuals at Kohlberg's preconventional and conventional moral levels. Method: Thirty members of Islamic State of Iraq and Syria (ISIS or Daesh) and Al-Qaeda housed in Kuwait's Central Prison completed four measures: the Armed Political Violence Measure, the Islamic Fundamentalism Measure, the Moral Judgment Measure, and Watson-Glaser's Critical Thinking Appraisal. Results: The results showed a significant negative correlations between armed political violence and both moral judgment and critical thinking. There was also a positive correlation between armed political violence and Islamic fundamentalism. The multiple regression analysis revealed that Armed Political Violence was associated with Worldly Rejection versus Worldly Affirmation (a Fundamentalism subscale) and Recognition of Assumptions (a Critical Thinking subscale) and accounted for 63% of the variance. The results also showed that those at the preconventional group were significantly higher in armed political violence and Islamic fundamentalism, and lower in critical thinking compared with those at the conventional group. Conclusions: To reduce armed political violence perpetrated by religious extremists, the field needs to better understand the moral framework that obliges people to participate in such violence. Moral stages might not necessarily protect a person from identifying with terrorist acts, and greater focus should be placed on the lack of critical thinking.