“In considerable detail and with admirable clarity, [Habeck] contributes one of the most valuable books on the ongoing Middle East—and world—crisis” (Booklist, starred review). After September 11, Americans agonized over why nineteen men hated the United States enough to kill three thousand civilians in an unprovoked assault. Analysts have offered a wide variety of explanations for the attack, but the one voice missing is that of the terrorists themselves. This penetrating book is the first to present the inner logic of al-Qaeda and like-minded extremist groups by which they justify September 11 and other terrorist attacks. Mary Habeck explains that these extremist groups belong to a new movement—known as jihadism—with a specific ideology based on the thought of Muhammad ibn Abd al-Wahhab, Hasan al-Banna, and Sayyid Qutb. Jihadist ideology contains new definitions of the unity of God and of jihad, which allow members to call for the destruction of democracy and the United States and to murder innocent men, women, and children. Habeck also suggests how the United States might defeat the jihadis, using their own ideology against them. “Concise and sober . . . Quite simply the best single volume currently available on this topic.” —Los Angeles Times “Knowing the Enemy is vital in the struggle of ideas.” —Theo Hartman, Centre for Research on Geopolitics “A level-headed, intelligent, thorough and accessible survey of modern Islamic militant thinking.” —The Guardian “[An] important and necessary new book . . . It demonstrates an insight and forthrightness rare among Western pundits.” —The New York Sun “A succinct and useful guide.” —The Wall Street Journal