Surrogacy has always seemed to me to be perfectly compatible with conservative values. It involves a carefully planned pregnancy designed to deliver a baby to two loving parents. There is very little chance the fetus will be aborted. Its soon-to-be parents are almost certain to be well off and won’t need to lean on the welfare state while raising their child. Surrogacy is, in other words, the least risky way to approach the inherently risky endeavor of reproduction.

But a cri de coeur published in the National Review on Monday reminds me exactly how wrong my assumptions are. For a certain subset of conservatives—most of them orthodox Catholics—surrogacy is a chief evil of modern sexual liberty, lagging behind abortion but keeping pace with gay marriage. Intriguingly, principled opposition to surrogacy isn’t even about homosexuality—though those who oppose surrogacy generally oppose gay parenthood as well. It’s about fidelity to relatively esoteric Catholic notions of natural law. And the larger question of surrogacy is poised to cause a catastrophic rift within the conservative movement as a whole.

To understand the deep ideological divisions surrounding surrogacy, you need only look to Louisiana, where the surrogacy debate has thrown conservative Republicans into a complex intra-party debate. In 2013, Louisiana Gov. Bobby Jindal vetoed a Republican-sponsored bill that would have legalized surrogacy contracts throughout the state, following pressure from conservative Christian groups. The bill’s sponsor then overhauled the bill, affixing amendments that satisfied conservatives’ concerns. But at the last minute, these groups decided the new bill was still fundamentally immoral, and Jindal vetoed the revised bill earlier this year. (Overcome by zeal, anti-gay activist Robert P. George promptly suggested Jindal would make a great president.)

Why do some Republicans want to legalize surrogacy contracts? Easy: Straight people, including straight men, need surrogates. Although some surrogacy opponents try to frame their argument as a fundamentally anti-gay one, this is a bit of a ruse. Gay couples represent only a fraction of all potential surrogacy clients; most people in need of a surrogate are infertile straight couples. Surrogacy opponents, then, may try to capitalize on existing anti-gay animus to further their cause—but really, their hostility to the practice is tethered to their broader enmity toward modern conceptions of sexual autonomy.

This animosity toward sexual liberty is the barely stifled undercurrent of pretty much every anti-surrogacy article out there. For a fringe group of conservatives, gay marriage and abortion are just the tip of the iceberg. What truly disgusts them is the whole array of modern sexual and reproductive practices, from egg donation and IVF to divorce and remarriage. To orthodox Catholics, the widespread acceptance of assisted reproductive technologies and non-traditional families is a grotesque violation of natural law and the start of a horrifying brave new world in which technology trumps humanity.

These terrors, of course, aren’t novel; they’re just a repackaged version of the same old anti-modern crusade conservatives have been waging since time immemorial. By capitalizing on our natural fear of the new, the right wing has been able to beat back advances in gay rights and women’s sexual autonomy for decades. But the anti-surrogacy campaign goes one startling step farther, catching straight couples in its net and castigating them for making deeply personal decisions that would seem to be nobody else’s business.

What we’re seeing here, then, is the beginning of the end of a hoary coalition, the hardcore Christian right. For a time, this righteous alliance was completely united in its opposition to various aspects of modern sexuality—but now that it’s setting its sights on something that plenty of straight couples need, that unity is about to crumble. The rift that recently developed in Louisiana is about to run through the rest of the country, splintering off the orthodox religious right from their more mainstream brethren. Thanks to the surrogacy debate, conservatives are beginning to realize how awful it feels to have your moral and sexual choices censured and restricted by the state. It’s a nasty revelation—but also an inevitable one. The Christian right has been maligning gays and women for long enough. It was only a matter of time before their holy hypocrisy boomeranged on their own self-interests.