Unless you live under a rock, you know there are those among us who think America should emulate Scandinavian countries. Apparently, Ivanka Trump is one of them.

Those who champion family leave, equal pay for women and affordable childcare believe that if women had financial support from the government, the way women do in other countries, America could finally move toward gender equality.

But a new study by the National Bureau of Economic Research puts that argument in the trash, where it belongs.

"Despite considerable gender convergence over time," note the study's authors, "substantial gender inequality persists in all countries. Using Danish administrative data from 1980-2013 and an event study approach, we show that most of the remaining gender inequality in earnings is due to children."

Those darn kids ruin everything. At least that's the takeaway at Slate. "Children are career killers for women," it says. And tradition, notes Jordan Weissmann, is "hard to budge."

Ironically, Weissmann laments that America is "woefully behind on parental leave and child care policy" but simultaneously, though perhaps begrudgingly, concedes "there’s only so much public policy can do."

It doesn't matter what kind of policies America adopts, just as it doesn't matter which policies the Swedes adopt. Women all over the world continue to put children ahead of career — which means gender equality, as feminists define it, is a futile goal. Mothers, as a rule, simply don't view their children as impediments to their careers. Rather, they view children as more important than their careers. They accept that trade-offs are part of life, whether they live in a free-market society like ours or under the democratic socialism that Bernie Sanders loves so much to promote.

Which means at the end of the day, parental leave will not fix inequality, even on the generous levels offered in countries like Sweden,

And as this new research proves, even that imbalance doesn't fix the inequality.

Perhaps it's time we listened to Clare Luce Boothe, who once said, "It is time to leave the question of the role of women up to Mother Nature — a difficult lady to fool. You have only to give women the same opportunities as men, and you will soon find out what is or is not in their nature. What is in women's nature to do they will do, and you won't be able to stop them. But you will also find, and so will they, that what is not in their nature, even if they are given every opportunity, they will not do — and you won't be able to make them do it."

Suzanne Venker (@SuzanneVenker) is a contributor to the Washington Examiner's Beltway Confidential blog. She is an author, Fox News contributor, and trustee of Leading Women for Shared Parenting. Her fifth book, "The Alpha Female’s Guide to Men & Marriage: HOW LOVE WORKS," was published in February.

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