American democracy still suffers from some of the rifts that opened five decades ago.

Until very recently, most older Americans would have agreed that, hands down, 1968 was the worst year in modern U.S. history. Events had been building up to combustible levels for several years, as race relations deteriorated, protests against the Vietnam War spun out of control, and a shrill debate about the state of American society reached toxic intensity.

As the year began, I was working as a reporter for a small-town newspaper in central Pennsylvania. The paper’s circulation area was in the northern reaches of the Bible Belt, and local political leaders took pride in having rejected federal funds from Lyndon Johnson’s War on Poverty.

But the paper’s political orientation stood to the right of its readership. The principal owner hated civil rights protests and flatly refused to permit coverage of a speech by James Farmer, a stalwart of the movement for racial equality, at the local college. The owner claimed to have evidence of Farmer’s Communist Party ties; in fact, Farmer was a committed democrat and apostle of nonviolence and racial integration, principles that earned him a reputation as an accommodationist among the younger generation of black radicals. Likewise, the paper refused to cover labor affairs, including the strikes that occasionally took place at steel mills and other local industries.

After Martin Luther King’s assassination, there was a series of closed-door meetings involving members of the family that owned the paper. Voices were raised, and the newsroom was in a state of tension. As…