In the 13 months since the Supreme Court overturned the Defense of Marriage Act, gay marriage advocates have been handed an unbroken string of judicial triumphs—continuing this week with another circuit court and another state attorney general landing on the side of equality. This winning streak might seem to represent the inevitable victory of the gay marriage movement’s passion and logic, and to some extent, it does. But it’s also the result of the anti-gay-marriage movement completely collapsing around its own terrible arguments.

As Yale Law Professor William N. Eskridge brilliantly argued two years ago, there’s really only one internally logical argument against gay rights: the idea that gay people deserve the state’s moral opprobrium. Yet this reasoning was functionally voided by the Supreme Court’s ruling in Romer v. Evans way back in 1996, when Justice Anthony Kennedy wrote that no law motivated primarily by animus against gays could pass constitutional muster. The animus test has its flaws, but it has largely succeeded in keeping baldly moralistic arguments—gay people are gross, or sinful, or sick—out of the courtroom.

Marriage-equality opponents, however, never quite got over the shock of seeing their most treasured argument foreclosed upon. If the state couldn’t justify anti-gay policies by insisting that it’s rational to dislike gays, what other argument could possibly suffice? The question became even more pressing after 2003’s Lawrence v. Texas, which struck down anti-gay sodomy laws on the theory that the 14th Amendment’s promise of “liberty” guaranteed gays a significant degree of personal autonomy. Once again, gay rights opponents were vexed: The court had just nullified their most populist argument—the notion that same-sex sex is a transgression against the laws of nature. What coherent justifications for anti-gay policies could possibly exist in a post-Lawrence landscape?

The answer, it turns out, is that there are none—none, at least, that aren’t driven by animus. A review of the failed attempts here is instructive. At various points, conservatives argued that every child deserves a mom and a dad; that gay people simply make inferior parents; that marriage isn’t marriage without penile-vaginal penetration; that legalizing gay marriage would lower birth rates; and, best of all, that somehow, allowing gay people to get married would cause more straight people to have children out of wedlock.

Are you snickering? So were the judges who had the pleasure of hearing these arguments spelled out in court. Doctors and scientists have known for years that children do just as well with two dads or two moms, if not a little better; in fact, the only disadvantage the children of gay couples face is the stigma foisted upon them by anti-gay conservatives. (Even conservative Utah has stopped arguing that gays make bad parents.) The notion that vaginal intercourse a true marriage makes, while fun to talk about, surely has no bearing on equal protection jurisprudence. (It’s also rooted in Catholic dogma and is patently ridiculous.) The birthrate claim is made up wholesale.

And the puzzling hypothesis that legalizing gay marriage will lead straight people to have more kids out of wedlock? Judge Vaughn Walker raised this point with a lawyer defending California’s Proposition 8, demanding to know “how permitting same-sex marriage impairs or adversely affects” straight people’s marriages. The lawyer had this response: “Your honor, my answer is: I don’t know. I don’t know.”

The problem here, of course, is that an honest answer—“your honor, we believe gay people will destroy the marital institution altogether”—would undermine the supposedly secular, animus-free nature of these arguments. In developing them, anti-gay activists began with a conclusion—gay people don’t deserve the rights that we straight people have—then worked backward, camouflaging each prejudiced premise with a supposedly neutral talking point. Under any kind of scrutiny, these theories instantly fall apart, revealing their bigoted, constitutionally impermissible core.

That’s what happened on Monday, when the 4th Circuit held that “apprehension and inertia” lie behind resistance to marriage equality. It’s what happened when Pennsylvania and Nevada’s Republican governors gave up on their states’ gay marriage bans, and when North Carolina, Oregon, Kentucky, Illinois, California, and Virginia’s attorneys general did the same. A good lawyer knows when she’s on the losing side of an argument. And stripped of their conservative Christian underpinnings, these arguments are blindingly, blatantly hollow.

And yet the inanity continues full-throttle, because gay marriage opponents have backed themselves into the corner they’ve always dreaded. They can’t give up their quest now—but they’re barred from citing the explanations that they truly believe, deep down, to be correct. The result is the current tailspin of idiocy, a shifting argument with rootless standards roaming from rationale to rationale in a desperate attempt to find shelter from the storm of progress swirling around it. It’s a pathetic display, but not an unpleasant one to witness. Stripped of all logic and reason, the argument against gay marriage has been reduced to gibberish. Enjoy the babbling while it lasts.