There is a dark side to religious devotion that is too often ignored or denied. As a means of motivating people to be cruel or inhumane— as a means of inciting evil, to borrow the vocabulary of the devout— there may be no more potent force than religion. When the subject of religiously inspired bloodshed comes up, many Americans immediatley think of Islamic fundamentalism, which is to be expected in the wake of the September 11 attacks on New York and Washington. But men have been committing heinous acts in the name of God ever since mankind began believing in deities, and extremists exist within all religions. Muhammad is not the only prophet whose words have been used to sanction barbarism; history has not lacked for Christians, Jews, Hindus, Sikhs, and even Buddhists who have been motivated by scripture to butcher innocents. Plenty of these religious extremists have been home-grown, corn-fed Americans.