Women's Equality Day comes but once a year. It's an opportunity to celebrate the brave women and acquiescent men who brought us the 19th Amendment, which was declared part of the Constitution on August 26, 1920.

Call me old-fashioned, but on this girl power holiday, I like to remember Susan B. Anthony's "Women Are Persons" speech—"It was we, the people; not we, the white male citizens; nor yet we, the male citizens; but we, the whole people, who formed the Union!"—and the painfully shy eighth grader who recited it with remarkable vigor in my classroom two years ago. (I'm a former teacher.) She got a standing ovation and, of course, an A.

For some, though, this day is an opportunity to rain sticky "statistics" on my look-how-far-we've-come parade. In honor of the anniversary of women's suffrage, Vanessa McGrady, for example, wrote about equal pay in Forbes, "I'm glad people are paying attention to the issue, but I'm beyond appalled that we need a day (and just one day? What about a year? Or a millennium?) to bring awareness to the wage gap between men and women, after decades of concentrated effort to right a man-made problem." She invokes the oft-floated "79 cents to the dollar" figure as pure fact and then loosely allows that this margin is more than halved by, conservatively, factoring in women's child care choices. Women's wage-earning lives are often, naturally, interrupted by motherhood.

The Independent Women's Forum, a beacon of liberty-minded and lady-directed economic ideas, shines the rare light of sense and responsible social science into this murky pay-gap story. Their findings, supported by the Department of Labor, show how an ill-considered progressive corrective to the wage gap would encourage burdensome litigation against employers—and, effectively, discourage private businesses from hiring and retaining married women and mothers.

Hillary Clinton's focal child care policy suggests she and her campaign understand that the fundamental reason for the purported pay gap is not so simple as "unequal pay for equal work," which she also shouts about. The Berned-over platform's proposed "human infrastructure investments" proudly borrow from Scandinavian socialism. The frigid promised lands are famous for publicly funded child care and generous parental leave.

Nima Sanandaji, Persian-Swedish economist and author of Debunking Utopia: Exposing the Myth of Nordic Socialism, notes that particularly in Sweden, "where women have made considerable progress in society as a whole, [they] are clearly underrepresented in executive positions."

In Sweden and other Nordic countries, female-dominated sectors, such as health care and education, are mainly run by the public sector. A study from the Nordic Innovation Centre, for example, explains: "Nearly 50 percent of all women employees in Denmark are employed in the public sector. Compared to the male counterpart where just above 15 percent are employed in the public sector. This difference alone can explain some of the gender gap with respect to entrepreneurship. The same story is prevalent in Sweden."

Sweden's awkward imbalance reflects our own "man-made" wage gap, which women's tendency to choose flexible careers (like teaching and blogging, say) widens. Whether we're socially conditioned or innately inclined this way, the imbalance only intensifies when a bloated nanny state like Sweden's provides a vast field of flexible, family-friendly public sector jobs. In other words, if more women mastering the universe is your idea of progress and equality, don't count on democratic-socialist policy to pave the way forward.