What is terrorism? Who are the terrorists? What direction will terrorism take in the future? What will the consequences be? The author provides some insights into these four questions, based on his definition of terrorism as violence that "recognizes fewer civilians" than other forms of warfare, and of terrorists as a mixed bag of "disparate groups and individuals whom history will judge to be murderers, or patriots, or lunatics." While the terrorists' record in achieving political goals is dismal, their tactics have been successful in terms of headlines captured; TV coverage; diversion of resources due to alarm; costs of protective measures; and intimidation of governments, compelling them to abandon their law enforcement function. Some future trends can be discerned: increasing links and cooperation between terrorists in various parts of the world; and, given the creation of new social vulnerabilities and new, sophisticated weapons, more spectacular and destructive acts.