ABSTRACT
Terrorism is often presented to the public as inexplicable. The apparent arbitrariness of bombings, kidnappings, assassinations, and hijackings contributes to an impression of pointless destructiveness. The difficult task of scholars is to make this phenomenon understandable. Over the past twenty years Irving Louis Horowitz has contributed to this endeavor both as a writer and as a publisher. Since the early 1970s, before the literature on terrorism had swelled from a mere handful of citations to thousands of books, reports, articles, and chapters, he has been convinced that terrorism is understandable and that the concept can be an explanatory variable, not merely a political label.1
