I traveled around the country as an elite swimmer for more than a decade, and I could never have imagined a world where men would be welcomed into the female-only bathrooms and locker rooms I used. I instinctively knew that separate spaces were for my privacy and protection. But as I have shared my own story about having to compete against a grown man in the pool, I’ve seen how broken our nation’s understanding of sex is.

It's come so far that even organizations that were once “pro-woman” have completely rejected the basic understandings of woman and womanhood.

The gender ideology madness must stop, both for the protection and privacy of women and girls and for the long-term health of the rising generation.

Earlier this year the National Women’s Law Center, an organization supposedly founded by women to protect women, filed a brief opposing my suit against the NCAA on the grounds that “woman” should be redefined to include men.

When leading “pro-woman” organizations are engaged in a campaign of lies about basic physiology and anatomy — when they support men more than they support women — we need leaders who are bold. We need leaders who speak out and refuse to cave to critics.

Last week, House Speaker Mike Johnson (R-La.) did just that. He sent shock waves through the media for saying something so painfully obvious that it would have gone unnoticed even a few years ago. Johnson simply said: Men are men, women are women, men cannot become women. He understands that the government should protect men’s and women’s privacy, safety, and opportunity.

For nearly all of congressional history, this sentiment was so widely understood that it did not need articulating. But in our modern world, where traditional definitions of sex have been conflated with completely flexible and ever-changing understandings of “gender identity,” Speaker Johnson might as well have set off a grenade.

His comments were made as all newly elected members of Congress were beginning their orientation in Congress. One of those new members is Sarah McBride, a Delaware man who says he identifies as a woman.

I know Speaker Johnson, and he is a man of principle and faith. Just a few months ago, he hosted a panel regarding Title IX protections and invited me, former Secretary of Education Betsy DeVos, Rep. Virginia Foxx (R-N.C.), and Independent Women’s Forum Chairman Heather Higgins. He was clear about his positions and criticized the Biden administration’s efforts to change the definition of “sex” to include “gender identity” under Title IX.

Johnson once again showed leadership last week on the critical issue of protecting women. He used his authority over the Capitol’s facilities as speaker of the House to ensure single-sex facilities would remain separated by sex and to protect women-only spaces.

This is not an attack on Rep. McBride (D), as some in the media are suggesting. In fact, Johnson noted that McBride is a duly elected member of Congress who deserves to be treated with dignity as a human being and with the respect that comes with high public office.

But McBride is also a victim of the modern gender ideology that says men can become women and that tells individuals suffering from gender dysphoria that the issue lies with their bodies, not with their minds. The treatments offered to these people can end in sterility, loss of sexual function, and numerous other devastating and irreversible medical issues.

The Independent Women’s Forum has detailed the stories of many detransitioners who have had their bodies mutilated by doctors who told them to take puberty blockers and cross-sex hormones and have healthy body parts surgically removed. Many of these detransitioned men and women are now suffering from intense regret along with permanent physical damage, but as they have spoken out and tried to warn others, they have been excoriated by the same left-wing media and activist class that has been demonizing Johnson’s decision to stand with women.

The gender ideology madness must stop, both for the protection and privacy of women and girls and for the long-term health of the rising generation. Right now, all Americans who care about the future and safety of their daughters, or nieces, or sisters, or cousins have a responsibility to speak up and reject the lies of our modern age that call men women and women men. Mike Johnson is standing up for women everywhere by taking a stand to keep men out of women’s bathrooms in the House. I hope his actions inspire leaders across the country to do the same.

Editor’s note: This article was originally published by RealClearPolitics and made available via RealClearWire.