Last Thursday an online tempest erupted when Hilary Rosen went on CNN to explain that she didn’t think Ann Romney was a worthy voice for America’s women because she “has actually never worked a day in her life.” The kerfluffle might seem familiar. Twenty years ago, Hillary Clinton came under fire for a remark she made during her husband’s presidential campaign, which many interpreted as dismissive of stay-at-home mothers.

“I suppose I could have stayed home and baked cookies and had teas, but what I decided to do was to fulfill my profession which I entered before my husband was in public life,” Clinton said – in 1992.

So why are mommy wars such a perennial?

Stay-at-home mothers fulfill society’s ideals of motherhood but are found lacking when measured against the world of work. Studies by Susan Fiske, Peter Glick and their colleagues find that college students rank homemakers’ competence as startlingly low, alongside the groups commonly seen as least competent: the elderly, blind and developmentally disabled. Adults (phew!) rank homemakers’ competence much higher, but most homemakers have encountered “Oh, you’re just a housewife” belittlement.

This makes them touchy. Mothers with jobs are touchy, too, because to the extent that they fulfill ideals at work, they fail to fulfill ideals of motherhood. When Americans are asked about the “good mother” and the “good father,” they find a lot of overlap, with one key difference: good mothers are seen as always available to their children.

So working moms are faulted for their failure to fulfill our ideals of motherhood, and stay-at-home mothers may be belittled for their failure to seen as go-getters.

Neither one of these judgments escapes either group of women. Thus stay-at-home mothers feel on the defensive because of felt criticism that they are “just housewives” and working moms feel on the defense because of the felt criticism that they are bad mothers. The result is a classic “difficult conversation.” Conversations become difficult when each side’s identity is at risk, which is certainly the case in mommy wars. Working moms protest, ‘Look, I worked, and my kids are just fine.’ Stay-at-home mothers protest, ‘I put my children first. What matters more to women than being good mothers?’ No wonder things get freighted fast.

Solutions?

For mothers, here’s the message. Stop fighting each other. Motherhood disadvantages stay-at-home mothers, whose contributions are regularly belittled not only at cocktail parties but in divorce courts, where judges often given longtime homemakers no more than three to five years “rehabilitative alimony.” Motherhood also disadvantages working women: as we have noted before, a mother is 79% less likely to be hired, 100% less likely to be promoted, and offered an average of $11,000 less in salary than an identical woman without children.

Women need to stop fighting with each other and band together with like-minded men to break the links between motherhood, belittlement, and economic vulnerability.

For feminists who (like me) are Democrats, there’s a different message. We need to never ever ever (again) get so invested in catering to our own insecurities that we defend ourselves by belittling other women. That’s not feminist, folks. And it’s a short path to squandering a key demographic we as Democrats need to win in order to keep the Presidency and defend all kinds of thing feminists hold dear – like the Lilly Ledbetter Fair Pay Act, for example, and Roe v. Wade. These things matter so much more than our personal choices about motherhood – because your kids are going to turn out fine. Mine did, and not because I did everything perfectly.

Seriously. The next time you’re feeling fragile about whether you’ve been a good mother, e-mail me. I will tell you that you’ve tried damn hard and have been a good-enough mother. It’s a hard, hard, hard job.

I guess that's the point.