Anyone who wants to understand what militant Muslims think has to understand what they read-and they read Sayyid Qutb, the intellectual father of Islamic fundamentalism. Qutb, an Egyptian literary critic and philosopher who was appalled by American decadence, gained prominence in the Muslim Brotherhood, was imprisoned by Nasser, and hanged in 1966. Through his death and prolific writings he became a martyr for the cause of political Islam. His work is virtually unknown outside the Muslim world, but Qutb is at the heart of the intellectual rationale for jihad and violence in the name of...