Books about the sixties have proliferated in recent years, but none has surpassed Nicholas von Hoffman's classic account of the 1960s counter-culture in San Francisco. "In the summer of 1967," he writes, "youth drew attention to itself by clustering in large numbers in most major American cities, where they broke the narcotics laws proudly, publicly, and defiantly. At the same time, they enunciated a different social philosophy and a new politics,...