There is little that individual employers can do about any of these issues. They can’t make men do more housework, or pick majors for women. Nor can they reasonably be asked to adjust their salary schedules to make up for those choices.

Yet the gender-gap discussion always centers on holding employers accountable. Earlier this year, The New York Times editorialized in favor of tougher laws for employers. Why? “At a time when women still earn, on average, only 77 cents for every dollar earned by men, there is a clear need for stronger steps to help close the gender gap.” The Times didn’t mention anything other than employer behavior that could explain that statistic — even though it’s only a small part of the story.

Obsession with the pay-gap statistic has led the National Organization for Women to support legislation to restructure the economy. Male-dominated occupations tend to pay more than female-dominated ones. In its press release about Equal Pay Day, the group called on Congress to force employers to change the pay scales for different jobs. The government would be invited to decide appropriate pay levels, one lawsuit at a time. The assumption is that employers’ sexism is what now determines which jobs pay more.

There is no reason to believe that. And there’s no reason to think that women will ever, on average, have the same preferences as men about combining employment and parenthood, or that they will want to become librarians and truck drivers at the same rate as men.

So we shouldn’t expect that 77 percent figure ever to rise to 100 — or even want it to.

Ramesh Ponnuru is a Bloomberg View columnist and a senior editor at National Review.