In some sense, it doesn't really matter how the Supreme Court rules on the gay marriage case it's hearing today. The culture war is over on this front, and gay marriage has won. Even if it loses at the Supreme Court this term, it will win in the legislatures . . . because it is already winning in popular opinion. Few people much under the age of sixty see a compelling reason that straights should marry and gays should not. For that matter, my Republican grandfather is rumored to have said, at the age of 86, "I think gays should marry! We'll see how much they like it, though."

At this point, it's just a matter of time. In some sense, the sexual revolution is over . . . and the forces of bourgeois repression have won.

That's right, I said it: this is a landmark victory for the forces of staid, bourgeois sexual morality. Once gays can marry, they'll be expected to marry. And to buy sensible, boring cars that are good for car seats. I believe we're witnessing the high water mark for "People should be able to do whatever they want, and it's none of my business." You thought the fifties were conformist? Wait until all those fabulous "confirmed bachelors" and maiden schoolteachers are expected to ditch their cute little one-bedrooms and join the rest of America in whining about crab grass, HOA restrictions, and the outrageous fees that schools want to charge for overnight soccer trips.

I know, it feels like we're riding an exciting wave away from the moral dark ages and into the bright, judgement free future. But moral history is not a long road down which we're all marching; it's more like a track. Maybe you change lanes a bit, but you generally end up back where you started. Sometimes you're on the licentious, "anything goes" portion near the bleachers, and sometimes you're on the straight-and-narrow prudish bit in front of the press box. Most of the time you're in between. But you're still going in circles. Victorian morality was an overreaction to the rather freewheeling period which proceeded it, which was itself an overreaction to Oliver Cromwell's puritanism. (Cromwell actually did declare a War on Christmas, which he deemed to be sensuous paganism.)

We've been moving away from the Victorian view of marriage for a long time, which means that we're probably due to circle back around the prudish front that drove Charles Dickens to lie when he left his wife for another woman.

The 1970s were an open revolt against the idea of the dutiful pair bond, in favor of a life of perpetual infatuation. The elites led the way--and now they're leading it back. Compare Newt Gingrich or John McCain to the new generation of Republican hopefuls. Jindal, Ryan, Christie, Rubio . . . all of them are married to their first wives. Jindal met his wife in high school, Christie in college. By their age, McCain was preparing for his first divorce, and Gingrich was just a few years from his second.

Meanwhile, it's becoming increasingly impossible to ignore the disastrous collapse of marriage outside the elite. It turns out that there aren't a diverse array of good ways to raise a child, as the progressive academics of the 1970s had suggested. Or at least, if there are, they don't include having children with an array of men you're not willing to marry, and who will subsequently drift in and out of your life. And that, in post-sexual revolution America, is increasingly the norm in many areas.

But one major and more dystopian feature of actual contemporary twentysomething life is conspicuously absent from small-screen depictions: parenthood. Hard as it might be for Hannah and Mindy—and their viewers—to imagine, most American women without college degrees have their first child in their 20s. These young women and their partners—who make up about two-thirds of twentysomething adults in the United States—are logging more time at the diaper aisle of the local supermarket than at the local bar.

This would not be such a big deal except for the fact that many of these twentysomethings are drifting into parenthood, becoming moms and dads with partners they don’t think are fit to marry or at least ready to marry. For instance, almost 1 in 2 babies—47 percent, to be precise—born to twentysomething women are now born to unmarried parents. In fact, twentysomething women now have the majority of children outside of marriage, which—given that 30 is the new 20—makes them the new teen moms.

The reality is that children born to unmarried twentysomething parents are three times more likely to grow up with a disorienting carousel of adults coming and going in the home, compared to children born to married parents. This kind of carousel, as sociologist Andrew Cherlin notes in his book The Marriage-Go-Round, is associated with higher rates of teen pregnancy, behavioral problems in school, and substance abuse. By contrast, "stable, low-conflict families with two biological or adoptive parents provide better environments for children, on average, than do other living arrangements."

Even as we're understanding it, we're losing the reasons to be suspicious of the old marital norms. When traditional marriage, with its expectations of monogamy and longevity, no longer means excluding gays, expect it to get more popular among affluent urbanites.

To be sure, it's already popular--affluent urbanites are now quite conservative in their personal marital habits. They've just been reluctant to shame those who don't follow suit. But with marriage freed from the culture-war baggage, we now have an opening for change. Think it can't happen? Consider the cigarette. It was shocking for a woman to smoke on in public in 1880, nearly mandatory in 1940, and increasingly shocking in 2013 (for either gender). I wouldn't be surprised to see out-of-wedlock childbearing follow a similar course.

The neo-Victorian morality will protect who you want to marry--male or female, or maybe even something in between. But the wider open marriage is, the less necessary it becomes to defend the right to carefree sex--or children--outside of marriage. One can imagine a Republican politician fifty years hence ruining his career when he throws over his husband and children for a younger man.

If I had to guess, I'd also put late marriage on the endangered list. I married at 37 myself, so I'm not judging, here. But if we want childbearing to take place inside marriage (and I think we do), then the average age of first marriage can't get higher; it probably shouldn't even stay so high. As that average age rises, you get two unwanted phenomenon on the tails of the distribution: babies born to unmarried parents at the low end, and couples who want children but can't have them on the high side. So the current upper-middle-class tendency to push marriage later and later while people finish their educations and get settled doesn't seem very stable to me--even before we consider the difficulty of finding a mate to match your settled life, which Keith Humphreys has dubbed The Problem of Grandma's Lamp.

Of course, predictions are hard, especially about the future. Nonetheless, here is mine: whatever the Supreme Court decides, gay marriage will soon be legal throughout the land. But this will not mean that we drive ever onwards towards greater sexual freedom--rather, it will mean quite the reverse. The sexual revolution is over. And the revolutionaries lost.