This report is intended to serve as a primer for Air Force officers who must gain a basic understanding of the phenomenon of terrorism. It addresses numerous issues touching on the definition, theory, tactics, targets, and effects of terrorism, and the threat that terrorism poses to the U.S. Air Force, which is both a potential target of terrorist actions and a potential instrument of preemptive retaliation. The author suggests that past doctrines, training, and practices do not apply in the war of terrorism. At the same time, we are not defenseless against terrorist attacks. They are not, and are not likely to be, seriously incapacitating. Terrorists can always inflict damage, but they cannot “win” unless they manage to throw their target into a state of hysteria. Despite their mobility, their fanaticism, their advantage of surprise, and their emotional impact, terrorists do not have the capability to inflict crippling damage on the U.S. military. However, the U.S. military will have to develop new capabilities and doctrines to meet the challenge.