The difficult, protracted war against terrorism has raised unsettling questions about the nature of Islam and its influence on America’s declared enemies. In The Two Faces of Islam, Stephen Schwartz, who has devoted years to the study of Islam, explains its complex history and describes the profound philosophical and religious differences that distinguish traditional beliefs from the radical sects that have sprung up over the past fifteen hundred years. He focuses on Wahhabism, the puritanical sect to which Osama bin Laden belongs. Founded in the eighteenth century by a radical cleric, this intolerant “Islamo-fascist” sect became the official creed of the Saudi Arabian state and has been exported to Moslem countries from the Balkans to the Philippines, as well as to Islamic communities in Western Europe and the United States.