Three experiments conducted in 1997 and 1998 explored individual responses to reported fictitious international conflict involving the United States and other nations. Participants escalated the conflictual level of their responses to repeated attacks. In Experiment 1, escalation of conflict was greater in response to terrorist attacks than to military ones. In Experiment 2, after the initial attacks, men were more conflictual in responding to terrorist attacks by a democratic nation than by a nondemocratic nation, whereas the opposite pattern was found for women. In Experiment 3, participants responded with a higher level of conflict to terrorist attacks on military targets than to attacks on cultural/educational targets. Participants with greater personality dominance showed steeper escalation of conflict in their responses across successive attacks. These results are interpreted within the framework of an image theory of international relations and an expansion of the democratic peace hypothesis.