President Barack Obama is proposing a cool solution to help close the gender pay gap, but it doesn’t hit at perhaps the biggest problem keeping women from earning what men make.

That problem? Life.

Women’s responsibilities outside of work — mainly looking after children, but also caring for sick and elderly family members — often keep them from taking on the kinds of jobs that would finally close the distance in pay between the genders.

That doesn’t mean that the gender pay gap is the result of some kind of real “choice” women make, according to Claudia Goldin, one of the leading economists studying the gender pay gap.

“Women aren’t choosing to make less,” she told The Huffington Post. Instead, they’re buying the flexibility to handle responsibilities outside of work, said Goldin, who is a professor at Harvard.

U.S. public policy is many years away from grappling with this.Obama announced a strong new policy Friday afternoon that’s intended to address the pay gap. Under his proposal, companies with more than 100 employees will be required to report data on pay, broken down by gender, race and ethnicity.

It reinforces efforts already underway at some progressive companies whose leaders have pledged to eliminate pay gaps with salary analysis. Probably the most high-profile of these is software maker Salesforce, which has already spent $3 million to ensure women and men are paid equitably at the Silicon Valley firm.

Certainly pay gaps within companies exist and are a problem. Black and hispanic women face even worse wage gaps than white counterparts. Firms should do everything they can to eliminate unfairness. And, of course, gender bias and discrimination play a role in the wage gap. It’s fair to say Jennifer Lawrence got a raw deal compared to her male peers. There’s all kinds of nutty bias against women that goes down at work.

Women get interrupted at meetings. They aren’t often taken as seriously as their male counterparts. They are deemed too aggressive or too meek and unfairly penalized in performance reviews.

There’s a long, infuriating list.

It’s obviously important that we have strong laws prohibiting clear gender discrimination. This week, progressive groups are advancing bills in several states meant to encourage equal pay for equal work, as Lydia DePillis writes in the The Washington Post. Much of the legislation focuses on pay discrimination within companies