From the mass weddings of Sun Myung Moon's Unification Church to the mass suicides at Jonestown, charismatic cults and their devotees have become facts of American life. Once exotic offshoots of the Sixties counterculture exciting suspicion, scorn, terror, and counter-terror (as in the brief vogue of "deprogrammers"), cults have grown so common and entered so many areas of public life--managing everything from roadside flower-sellers to major metropolitan...