David Brooks recently wrote a piece with the provocative headline “The nuclear family was a mistake.” The article is thoughtful, and it hits on many important points. The central argument is that our culture has weakened the ties of extended families and neighborhoods.

The result, Brooks argues, is this: “The shift from bigger and interconnected extended families to smaller and detached nuclear families ultimately led to a familial system that liberates the rich and ravages the working-class and the poor.”

This is a specific instance of a broader truth: The shape of modern American culture and the breakdown of old norms and constraints over the past 60 years have created a culture that liberates the elites and ravages the working class and the poor.

This is especially true of our hypermobile society, where individuals are free to move around. This is especially true of our increasingly gig-oriented economy. This is especially true in a time of ubiquitous internet and smartphones.

It’s also true of our retreat from marriage.

Our culture has declared that marriage is no longer the building block of the family and the community. It’s perfectly fine to have kids together without getting married, the culture teaches. It’s perfectly fine to live together for a long time without getting married, we are told.

Of course, everyone ought to be free to live as he or she pleases. But a culture in which marriage has a weaker pull will be a culture in which the vulnerable do worse. The rich might be able to handle the tumult of an unmarried world. For one thing, the college educated are much more likely than the working class to get married and less likely to get divorced.

For another thing, the elites are more likely to have other advantages, such as money, connections, and stable work, that can act as supports in the absence of marriage.

Michael Bloomberg can live his life however he wants. (I wish he would extend that same liberty to the rest of us.) But we in the media ought not celebrate his 20-year relationship with his lady-friend whom he won’t marry.

The Washington Post kind of does celebrate Bloomberg’s relationship with Diana Taylor. Their nonmarital relationship supposedly shows she is “unfettered.” It is “a testament to … her independence.”

“Their relationship is not new, and it runs deep,” the Washington Post writes, “but it isn’t bound by law or religion.”

Taylor states that “nobody’s come up with the language around what we are.” How liberating.

According to the Washington Post, this tradition-flouting independence is part of “lifting up women as individuals — not as marital appendages, nurturing multitaskers or a voting bloc of uteri.”

Again, this may be great for Mike and Diana. But where unmarried cohabitation is more common, the working class, there are plenty of reasons to think it’s bad news for the woman, the man, and especially the children.

Richard Reeves and Eleanor Krause at Brookings report that “two-thirds of cohabiting parents split up before their child reaches age 12, compared with one quarter of married parents."

And for people who aren’t Michael Bloomberg, cohabitation often leads to serial cohabitation. Scott Stanley and Galena Rhoades at the Institute for Family Studies point to research showing “that serial cohabitation is strongly associated with economic disadvantage among unmarried couples, lower odds of marriage, and increased odds of poor marital outcomes, but serial cohabitation is growing rapidly among different population groups.”

In short, marriage provides stability. Nonmarriage creates instability. Instability might seem like freedom to the wealthy, but it’s dangerous for working-class women and their children.

If "the nuclear family was a mistake," the retreat from marriage was a bigger one.