In some ways, the statistic that made headlines this week—women are now the main breadwinner in forty per cent of households with children, according to the Pew Research Center—was not a big surprise. Two much discussed recent books, Liza Mundy’s “The Richer Sex” and Hanna Rosin’s “The End of Men,” chronicle the phenomenon of women outearning their male counterparts, and if we love our Mad Men more than ever that’s in no small measure because we know they are never coming back.

What did seem anomalous were some of the attitudes revealed in the broader Pew analysis. About half of the people surveyed said that children were better off with mothers at home (only eight per cent said the same for fathers). Three out of four said that the increasing number of working mothers made it harder to bring up children and half said that it also made it harder for marriages to succeed. I asked Hanna Rosin what she thought of the apparent disconnect between how people live and how, in many cases, they say they want to live (thirty-two per cent of the mothers surveyed said that their own preference would be to work full time, up from twenty per cent in 2007) or what they think might be better. Rosin’s view was that the attitudes were largely irrelevant: they were bound to change, she said, and they “reflected more a lingering attachment to a certain ideal”—the way we in America pay lip service to traditional family values—than “a measure of how we want to live and definitely not of how we do live.”

It does seem that these attitudes are evolving. In 1997, an even larger percentage of Americans said that women working outside the home made child-rearing and marriage more difficult. In the current survey, eighteen-to-twenty-nine-year-olds were more upbeat on the subject than people thirty and older. Sixty per cent of the younger group thought that mothers working outside the home put a greater strain on child-rearing, for instance, compared with seventy-eight per cent of the older group. Maybe some of that differential can be attributed to youthful optimism, and the eighteen-to-twenty-nine-year-olds will be just as grumpy when they’re older, but some of it surely represents a generational shift.

There might be something else going on, too. When people talk about the difficulty of rearing children today, they may actually be talking about economics and about work. Life is harder when mothers work outside the home because, obviously, there’s more to do in the same amount of time. That’s an existential reality and it ought to banish forever, please, the wretchedly misleading ideal of “having it all.” (Just when you think it’s finally been cudgelled into submission it pops up again, as yet another panel title or column opener.) But life is also stressful and often demoralizing in twenty-first-century America because we all live under a speeded-up, coercively multitasking, vacation-poor, debt-burdened, harsher, and less forgiving form of capitalism than do the citizens of many other industrial countries, and than we ourselves lived under for much of the late twentieth century. (See George Packer’s new book, “The Unwinding,” for an eloquent treatment of how we got there.)

Those realities are even more crushing for the women who make up the majority of the new female breadwinners: single mothers and, especially, never married single mothers. When you look at the Pew study, or any number of studies like it, solely through the lens of gender, it’s actually a pretty rosy picture. Many women have more education, more independence, and more reasonable hopes for an egalitarian partnership than they ever have in American history. If you look at it through the lens of class, the view is different and less uplifting.

The breadwinning women represent two distinct groups: single mothers, who are more likely to be black or Hispanic, young, and less educated, and who have a median household income of twenty-three thousand dollars; and married women who outearn their husbands. Women in the latter group are more likely to be white, college-educated, and somewhat older; their median family income is eighty thousand dollars. At the tip-top of that group are the households featured when, say, New York runs an article on female breadwinners (“Alpha Women, Beta Men”), and the details are all about town cars and nannies and sex lives that need perking up when the wife earns more on Wall Street. In the middle are married (or divorced) mothers who mostly make it all work, and mostly appreciate the freedom they have to do so, though they may be tired all the time.

Among the single mothers, on the other hand, there is a growing subset of women who have never married (forty-four per cent in 2011), and this group is still younger and less educated, and thus more likely to be in poverty or fall into it than single mothers in general. They’re a vulnerable population in a pitiless economy, and it’s hard to put a triumphal feminist spin on their story.

Illustration by Joost Swarte.