It’s now okay for a man to hit a woman.

That, in effect, is what a mixed martial arts league decided when it allowed Fallon Fox, a biological male, to fight as a woman simply because he identifies as one.

And the consequence of this decision?

Fox sent female fighter Tamikka Brents to the hospital with a broken skull and a concussion. Brents needed seven surgical staples to bind her wounds. The battered woman, a trained fighter herself, said of her match with Fox, “I’ve never felt so overpowered in my life.”

Twenty years ago, if a man hit a woman so hard that he sent her to the hospital, he’d be in prison. Now he can get paid for it.

Today we are told that male and female are one and the same.

This denial of male-female differences has led to the astonishing belief that men and women are not born male or female; they are whatever gender they say they are. Facebook went so far as to offer its users over 50 genders to choose from. Know what a “demi-boy” is? Me, neither.

The idea that gender-identification is now a personal choice might sound enlightened to some, but it’s actually a very anti-scientific view of one of the essential facts of life: men and women are inherently different. Their brains are different, their hormones are different, their chromosomes are different, and, of course, their bodies are different.

No amount of peer-reviewed papers from gender studies departments can change this. But that won’t stop the progressive elites who run our universities, news media, many of our biggest companies, and even our high schools and elementary schools from trying.

For their efforts, women will pay an especially high price.

That’s because the men-and-women-are-the-same argument invariably leads women to be judged against a male standard. Or, to put it another way, to be more of a woman, a woman has to be more like a man.

She has to want to have casual sex like a man; to serve in combat like a man; to pursue a career with single-minded intensity like a man. Of course, there are exceptions, but the overwhelming majority of women aren’t seeking casual sex; don’t have the physical strength of men; and don’t share the same work-life priorities as men.

Ironically, this quest for sameness is occurring at a time when science is telling us, more emphatically than ever, that we are different. So, what your grandmother took for granted – men and women are different – science now confirms.

But there is no room for science in, say, stores like Target or Toys R Us, where toys are no longer divided into the boy section and the girl section. Or in a North Carolina school district, where students can no longer be called “boys and girls” but only “students.” Or in college dorms, where co-ed bathrooms and even co-ed bedrooms are increasingly common.

For the tiny percentage of people who experience gender dysphoria, we should have nothing but compassion. We should do everything we can to help them and protect their dignity, but we don’t need to overturn biologically defined sex differences to do so.