A few years ago, Melissa S. Kearney got into a taxi cab and asked the driver about a photo of a young girl on his dashboard. The driver confirmed it was his daughter and then proudly showed her more pictures. The girl lived with her mother, he explained. Kearney, a professor of economics at the University of Maryland, asked why he didn’t live with them. “I don’t know,” he said. “We talk about it. If we save up some money, we might get married.” She pressed the issue, acknowledging that she had a professional interest in the subject: “I don’t mean to pry but if you guys get along and you both love your daughter, why don’t you live together as a family?” To which the man finally replied, “Did my mom send you or something?”

Marriage has been on the decline for decades now. As Kearney writes in her book The Two-Parent Privilege, “in 2019, only 63% of children lived with married parents, down from 77% in 1980.” The truth is that not many mothers, let alone economics professors, are even bothering to harass their adult children about tying the knot. And in principle, Kearney doesn’t have a problem with that. She says she likes being married herself and sees emotional and psychological benefits to the institution. But when it comes to addressing how the presence of two parents in a home affects children, she assures readers, “I answer these questions as an economist, not as someone with a moral or value-laden proposition.” In fact, she says, “it is really challenging to discuss the topics of marriage and family without it feeling like a conversation about values.” She hopes that “we can take them out of the intractable culture wars” and “debate them.”

For those outside the academy, like the taxi driver, this challenge might seem like a low bar. Why not debate the benefits of marriage? Lots of people may at some point wonder about the choices they should make in life or what effect living with a single parent has on children’s long-term prospects. To those who work in higher education, this task is all but impossible. How can you support this patriarchal institution, let alone render judgment on whether one family structure is better than another?

In her book, Kearney makes the case that conservatives have been making for years—that growing up in a single-parent home, particularly one in which the parents have never been married (not one resulting from death or divorce), has a detrimental impact on children and how they develop as adults. “Children in two-parent homes tend to live in homes with a higher level of income and have more time with their parents than do children from single-parent homes,” she writes. Nor is it just correlation. As Kearney explains, “data show sizable gaps in the outcomes of children who grow up with married versus unmarried mothers, even when the married and unmarried mothers are the same age and have the same levels of education.”

From Charles Murray to Robert Putnam, Thomas Sowell to Glenn Loury to Brad Wilcox, it’s hard to think of a serious book about the problems of income and racial inequality in America that hasn’t wrestled with the decline of the two-parent family. We should welcome to the fold anyone who has come around to this view. But Kearney’s diagnoses of the causes of these problems is incomplete, and what results is a prescription for change that is misguided and most likely ineffective.

Let’s start with the causes. The rise in nonmarital childbearing is first and foremost the result of changing social mores. The sexual revolution—including birth control, widely available abortions, and the disappearing stigma against bearing children out of wedlock—made single motherhood a real possibility for women. But what about the economics?

Kearney asserts in no uncertain terms that government payments did not contribute to the problem: “To argue…that the rising incidence of one-parent households in the U.S. has been driven by the availability of generous welfare benefits is simply untrue and unfounded.” She cites, among other evidence, that the welfare reform of the 1990s “did not appreciably affect marriage and birth rates, and the prevalence of mother-only families has continued its steady upward climb, despite the legislation’s wide-reaching changes.”

The flaw in this analysis is that she is using evidence from a time far advanced from the moment the genie of single motherhood escaped from the bottle. Yes, it’s possible that tightening welfare requirements in the 1990s—trying to recall the government’s replacement of the man in the home—did nothing to improve the marriage rate. But it’s also possible that, by that point, social mores were so entrenched that nothing would fix the problem.

Weirdly, Kearney makes this point herself in a different context. Rather than welfare programs undermining marriage, men’s marriageability—their inability to earn a good living—is one of the reasons they are not marrying, she argues. But then she notes that increasing men’s earnings today doesn’t seem to have the effect she hoped. She cites a study she oversaw in a community that was affected by the fracking boom. Suddenly men in the area were able to earn a lot more money than they had before. While she and her colleagues found an increase in the overall birth rate—“when people experience an increase in income or wealth, they tend to have more children”—the increase in births “occurred as much with unmarried parents as with married ones.” By contrast, during the 1970s Appalachian coal boom, more people got married and had kids inside marriages, but the number of births outside of marriage didn’t budge. By the time of the fracking boom 30 years later, everyone had accepted out-of-wedlock childbirth as perfectly acceptable. So why get married?

Perhaps because Kearney wants to stay out of the “culture wars,” she is unwilling to place any blame for current social mores on anyone in particular. There is no acknowledgement that the elites who are still getting hitched at virtually the same rate they were 50 years ago are the ones who promoted the expendability of marriage.

So how to fix this problem? If we do care about marriage because two-parent families promote better outcomes for children—not, heaven forbid, for any moral reason—is there anything we can do? Despite Kearney’s acknowledgement that neither the level of government spending nor private earning seems to move the needle very much on the likelihood that people will marry, she goes on to recommend “a massive infusion of federal resources into public universities and community colleges that educate and train millions of Americans each year.” She also recommends an expanded earned-income tax credit. She notes that “if we wish to promote marriage in the U.S., we should work to address the reasons why so many men seem to be less than ideal marriage partners.”

Similarly, Kearney recommends “criminal-justice reform” even as she acknowledges that many kids are actually better off when their parents are in jail. She cites one study showing that “children whose parents are incarcerated—due to a randomly assigned judge’s propensity to incarcerate convicted criminals—are substantially less likely to engage in criminal behavior before the age of 25.” Another study she cites shows higher educational attainment for kids whose fathers have been incarcerated (again due to randomly assigned judges). Removing criminals from the home has a good influence, and seeing a father imprisoned may actually have a deterrent effect.

But Kearney cannot help herself. Since there is a list of liberal prescriptions for the problems of disadvantaged people in the United States, she must offer them up even after explaining why those prescriptions won’t work.

Fair is fair: We don’t know what will work. But it is striking that Kearney never mentions the possibility of teaching kids the benefits of marriage. Perhaps simply opening up the conversation in the academy is as far as she can go without finding herself exiled from academia. Even as Kearney seeks to maintain her standing in her narrow world, Ian Rowe of the American Enterprise Institute has been going around the country trying to get schools to teach the “Success Sequence”—letting kids know that if they graduate high school and get married before having children, their chances of landing in poverty will be almost nil. Yes, of course, it will sound a little preachy. And advocating it may come dangerously close to “the culture wars.” But as long as we’re alerting college faculty to the benefits of marriage, we might as well tell the kids. And any taxi drivers, too.