Are we unraveling?

The center is not holding.

We are not a country in open revolution. We are not a country under enemy siege. We are the United States of America in the sticky summer of 2016, and the market is up and the unemployment rate is low and the president’s approval ratings are solid and it could have been a moment of brave hope and national resurgence, but it is not, and from the grandstands at Trump rallies to the streets of Dallas to the mad world of social media everyone knows that it is not.

The alert reader may have noted that I’m plagiarizing here: Those are the opening lines, condensed and somewhat altered, of Joan Didion’s “Slouching Toward Bethlehem,” written just as America entered the maelstrom of the later ’60s and the ’70s.

History rhymes rather than repeats; we are not reliving the widening gyre that Didion discerned. But there are echoes and recurrences linking this difficult moment to the American berserk of two generations back.

Now as then there is urban unrest, a sudden rise in homicides, tensions between protesters and cops; even white nationalism is re-emerging from its post-segregation sleep. Now as then there is campus activism, the New Left reborn as Social Justice Warriors. Now as then there is a spate of domestic terror attacks. Now as then — much more now than then, in fact — there is a pervasive mistrust of institutions, a sense that the country is rotting from the head down.

Our personalities echo the past as well. Donald Trump as George Wallace. Bernie Sanders as Gene McCarthy. Hillary as the Democrats’ own Richard Nixon. Even Pope Francis, our era’s defining religious figure, is very much a character out of Catholicism’s 1970s-era civil wars.

There are also demographic echoes. The millennial generation has just overtaken the baby boomers as America’s largest cohort. Like the boomers, they’ve been shaped by a communications revolution (TV then, the internet now), various sexual revolutions (gay and transgender rights, online dating, ubiquitous pornography), a retreat from churchgoing and family formation (the U.S. birthrate is scraping its 1970s-era lows). And millennials are in roughly the same place in the generational life cycle as the boomers were in 1970 — the 1990s were their prosperous childhood Fifties, 9/11 their Kennedy assassination, Obama-era liberalism their Great Society — and we could be entering their dark wood, their crisis years.

But now for a reality check, a reminder of the stark differences between Nixon-era America and our own. There is no Vietnam War, no draft, no Weather Underground, no spate of political assassinations. There is no massive crime wave, no urban collapse, no surge in social pathology. Our campus protests are more “days of wounded self-righteous hypersensitivity” than days of rage. The millennial generation seems atomized but relatively well-behaved, their passions channeled into virtual realms (Twitter fights, video games, porn) rather than the streets. The post-Ferguson spike in homicides is real, but the generation-long decline in violent crime is still the more important social fact.

As grim as race relations can seem, the Dallas shootings took place in a country with a two-term black president, in a state where conservative politicians backed sentencing reform, in a city where a black police chief has cut crime rates and complaints of police brutality. These are realities that even an ugly spasm of violence is unlikely to undo.

Such is the case for relative optimism in the face of the present feeling of unraveling.

But optimism only carries you so far. I would rather not repeat even part of the national nervous breakdown that “Slouching Toward Bethlehem” saw coming, not least because many of our institutions never fully recovered from that era’s crises.

The chaos of the Nixon era enfiladed a culture with stable-seeming families, healthy civic life, well-attended churches, trusted public institutions — a culture in which leading Republicans and Democrats still seemed to like one another, in which civil rights activists and white Southerners shared a common theological tradition, in which wages had been rising for a decades while divisions of class and ethnicity diminished.

Whereas our present nervous breakdown is happening in (to borrow the title of Yuval Levin’s excellent new book) “a fractured republic” — a society where elites are widely loathed, where the political parties are polarized and one of them is so hollow that a rank demagogue could seize it,where diversity and distrust have risen together, where wage growth has been disappointing, where families are fragmented and churches and civic organizations are in eclipse, where the metaphysical common ground provided by the old Mainline-Protestant consensus has all but disappeared.

The late 1960s and 1970s weakened many instruments of American consensus, many institutions that seemed to guarantee stability. We’ve been muddling through without them ever since, often confounding pessimists along the way. We’ll probably muddle through again.

But still — may the cup of crisis pass from us, and soon.