Looking at these trends from a broad perspective, Ryan Enos, a political scientist at Harvard, also wrote me by email:

We need to address the underlying premise that there is a rise in social disorder. That claim does not hold up to scrutiny, in both the long and short term. In the United States and many other parts of the world, the last two decades have seen a remarkable decline in many of the most visible signs of social disorder.

Enos continued:

You can see that many of these improvements in the quality of life have coincided with the creation of the modern liberal welfare state and many of place that enjoy the least social disorder are, in fact, places with leftist political systems that provide for social welfare.

Perhaps most confounding to social conservatives are the findings of a September 2018 study by the Federal Reserve Bank of St. Louis, “The Bigger They Are, The Harder They Fall: The Decline of the White Working Class.” A key conclusion:

Uniquely among major socioeconomic groups, the white working class decreased in absolute numbers and population share in recent decades. At the same time, the five measures of well-being we tracked all deteriorated for the white working class relative to the overall population. The shares of all income earned and wealth owned by the white working class fell even faster than their population share.

Put another way, the white working class — the segment of the population with the weakest ties to, if not outright animosity toward, liberalism, feminism and other liberation movements — has, in recent years, experienced the strongest trends toward social decay.

Or look at it this way: The white working class constituency that would seem to be most immune to the appeal of the cultural left — the very constituency that has moved more decisively than any other to the right — is now succumbing to the centrifugal, even anarchic, forces denounced by Barr and other social conservatives, while more liberal constituencies are moving in the opposite, more socially coherent, rule-following, direction.

“The broad-based decline that is unique to the white working class may be due in part to the group’s loss over time of advantages it once enjoyed relative to those of nonwhite working classes,” according to the authors of the report:

These included more years of education and plentiful high-paying jobs available in white working class communities. And, as the explicit discrimination minorities faced in the workplace has diminished, so has the advantage that it had given the white working class.

While in absolute terms the white working class — those without college degrees, in pollster shorthand — have higher levels of marriage and cohabitation, homeownership and self-reported health ratings than members of the black working class, the trends are downward for whites and upward for African-Americans.

Comparing the periods of 1989-98 to 2010-2016, the Fed found a 2.2 percentage point decrease in marriage and cohabitation rates for whites without degrees, from 59.5 to 57.3 percent, and a 5.4 percentage point increase for blacks from 32.1 to 37.7 percent. The percentage of whites reporting good health fell by 5.9 percentage points while rising 1.7 points for African-Americans.

The most telling critique of the claims of social conservatives is that their single-minded focus on the destructive forces of liberalism offers a facile (and erroneous) answer to developments that do not fit simple categories of good and evil.

Isabel Sawhill, a senior fellow at Brookings and author of “Generation Unbound: Drifting into Sex and Parenthood without Marriage,” emailed the following to me:

Some people believe that humans are born good and are only later corrupted by society. They emphasize the importance of a society that collectively helps each individual achieve their inherent potential. Others believe that individuals are inherently flawed, often ill-disciplined, weak-willed, and capable of evil as well as good. They emphasize the importance of social structures that help people, in the words of Edmund Burke, “to put chains upon their appetites.”

Under current conditions of stark political polarization, these two sides are at loggerheads. Sawhill argues that:

What a functioning and tolerant politics would permit is a negotiated settlement of this dispute. We would devise institutions and norms but also laws and practices that bring out, in Lincoln’s famous words, the “better angels of our nature.”

What are some of the roadblocks to “a functioning and tolerant politics” that could produce a “negotiated settlement”?