Efforts to explain the character and mental makeup of terrorists present many problems. While it is widely recognized terrorism cannot be defined precisely, research continues to discover underlying causes in the makeup of the terrorist personality. Over the past decade, many social scientists have explored economic theories of rational choice in an attempt to explain criminal and deviant activity. Psychologists and sociologists have looked at differences in orientation, intelligence, and temperament, as well as differences in social circumstances, among persons who do or do not frequently break the law. Socioeconomic perspectives contribute to the understanding of terrorist behavior and supplement many approaches that rely almost entirely on references to socioenvironmental factors. Psychosocial dynamics of terrorism indicate an individual must "morally disengage" in order to participate in indiscriminate violence. Terrorist organizations and their ideological machinery may be seen as self-exonerations needed to erase prohibitions against violent behavior and hate. Regulatory psychological mechanisms can be neutralized in several ways by blotting out personal agency in harmful activities, by acquiring attitudes that disregard or misrepresent detrimental consequences of one's actions, by blaming or dehumanizing victims, and by re-construing one's behavior as serving morally desirable purposes. Violent conduct may thus be justified by the rhetorical discourse of terrorist groups and through the diffusion of responsibility. The role of ideology in driving terrorist groups is discussed, and accountability and the problem of punishment are also examined. 38 references, 4 footnotes, and 1 figure