At the end of the last century international terrorist groups declared war on the United States. Rather than pursue this war using conventional means, terrorist tactics have been employed. Terrorism represents psychological warfare, not traditional military combat. Threats of assassination, bioterrorism, and even nuclear detonations have been used. Numerous attacks have subsequently been realized against both domestic and international American targets. Winning the war against terrorism means acknowledging and responding to the psychological dynamics inherent in this form of warfare, as well as the military and law enforcement aspects of the war. Consistent with Caplan's notions of preventive psychiatry, the fight against terrorism must occur on three levels: (1) prevention of the terrorist attacks themselves, (2) mitigating the adverse psychological impact of the persistent threats of terrorist acts, as well as the terrorist attacks when they do occur, and (3) psychological treatment of the lingering adverse effects of threatened or actualized terrorist attacks. The preplanned and/or coordinated psychological efforts to counteract terrorism and prevail in any given war against terrorism shall be herein discussed and subsequently referred to as "psychological counterterrorism."