My first mommy date—you know, those painstakingly-dressed-for occasions you hope will turn the mother of your child’s new best friend into your best friend, too—also gave me my first taste of the shame that makes the mommy wars so bitter. Tali’s husband worked on Wall Street, she stayed home with the children, and the playroom in their restored Victorian on a lake in Westchester was photo-spread perfect. There was an expansive, carpeted space for our toddlers to run wild in, an air-hockey table, a big-screen computer, Legos, kindergarten-grade wooden blocks, and a play house, all of it neat on a Wednesday afternoon despite there being no housekeeper in sight.

And what did this particular messy working mother feel? Pure envy: real-estate and clean-house envy, attentive-mother envy, and, when I saw her lovely kosher kitchen, Jewish envy too. Despite sending my kids to a Jewish school, I’d never quite managed the exhausting logistics of kashrut.

Getting over all this, I discovered that Tali was the child of Holocaust survivors, themselves the only living members of their families, and that, despite a wide circle of friends and an active synagogue life, she had the air of a person profoundly alone in the world. I figured that this had more to do with her history than her present situation, and that family life was her consolation. But she told me that she’d left her job in investment banking when she’d had her second child only because when she’d had her first, she’d gone part-time, which had meant working 40 hours a week instead of 60. In other words, five days a week, she had left her house in New Rochelle at 7 a.m. and returned from the city at 7 p.m. For any mother, let alone one who had obviously missed out on the warmth of a large family growing up, this would be hard to take.

To understand why female lawyers, doctors, or bankers quit work to stay home, don't search their souls. Look at the structural realities of the workplace.

The women I met through Tali were also mostly former high achievers with professional degrees—smart, appealing, non-helicoptering, non-Desperate Housewives-like, full-time, suburban mothers. They were the kind of women profiled by Lisa Belkin in her famous (or infamous) 2003 “Opt-Out Revolution” article in the New York Times Magazine; by Judith Warner in her 2005 book Perfect Madness; and by Lisa Miller this week in “The Retro Wife” in New York magazine—to give just a few notable examples. These tales of handsomely educated and perfectly sane members of my sex who abandon great careers for children have become so common they constitute a genre of their own. Some of these pieces (or books) explain women’s flight from the professions as the waning of feminist ideals from one generation to the next; others blame the rise of over-mothering, attachment parenting, and other trends of that ilk; some cite all of the above. Miller’s piece introduces “neo-traditionalism,” which she defines as a rejection of feminist definitions of success. In many such essays, Betty Friedan appears as a touchstone, used to show how little has changed since she wrote The Feminine Mystique, or implicitly chided for failing to see how intractable work-life balance would prove to be. Each writer accurately characterizes their subjects’ lives and is right about the trend they represent and is by no means wrong about the pleasures and comforts of the stay-at-home life. And all of them, in my opinion, miss a key point.

To understand why female lawyers, doctors, bankers, academics, high-tech executives and other, often expensively pedigreed, professionals quit work to stay home, you need not search their souls for ambivalence or nostalgia. In fact, searching their souls guarantees that you won’t get the story, because it’s not to be found in individual decisions and personal stories, which are always complicated and hard to parse, but in the structural realities of the American workplace. And by this I don’t just mean the family-unfriendly policies of the kind Marissa Mayer is accused of advancing—though refusing to let workers telecommute doesn’t help, and let’s not even talk about how few American companies have on-site child care or adequate parental leave. I mean that among the professional and managerial classes, success at work requires more hours in the office, more hours on the computer at home, more trips out of town, and a much less predictable schedule than it did in Betty Friedan’s day. The life of a Joan or a Peggy at an advertising agency looks almost easy by comparison.