There’s a chilling image from my youth that I’ve never been able to scrub out of my mind. It might not seem at first glance to amount to much. It was a blue spiral spray-painted on our street, a sort of insect with enormous eyes, with a caption suggesting LSD. In those days, the newspapers were filled with war and rumors of worse than war—of the wholesale collapse of the social order. It was when the Students for a Democratic Society engaged in their violent demonstration against that inoffensive, old-fashioned liberal Hubert Humphrey at the Democratic National Convention in Chicago. “Off the pigs,” cried the Black Panthers, whose tongues were not in their cheeks when they said it; rather their thumbs were ready to cock their pistols if any “pig” of a policeman were to get in their way.