The September 11th attacks left the world stunned, angry, and uncomprehending. When it became clear that they had been committed in the name of Islam, people struggled to learn more about the religion used to justify these acts. In this level-headed and authoritative book, John L. Esposito, one of the world's most respected scholars of political Islam, elucidates the teachings of Islam -- explaining Quran, the example of the Prophet, and Islamic law regarding jihad, the use of violence, and terrorism. He chronicles the rise of extremist groups and examines their frightening worldview and tactics. In a new Preface for the paperback edition, the author discusses the changes that have occurred since 9/11 -- including the continued threat of terrorism, the American-led war against terror, and the exponential growth of anti-Americanism. Book jacket.