“If you’re against gay marriage, is that the same as racism?” asks Slate’s William Saletan. His answer is “no.” The question is part of a larger debate that’s recently taken on new fervor in what may seem like the twilight of the fight for gay equality—a question Saletan asks in a related post: “Is everyone who opposes gay marriage a bigot?” He also answers that question “no.”

Much of the recent debate has followed from the flap over a New Mexico photographer who was sued for refusing to serve a gay couple, which together with some similar cases prompted several states to consider bills protecting religious-based discrimination. Saletan does not support these bills—not remotely. (He also favors same-sex marriage.) In fact, the bills have been widely opposed by both the left and the right. But he supports the broader position that opposing gay marriage is respectable and a less pernicious position than racism, a view with a surprising number of defenders.

They range from social conservatives like Ross Douthat (who called comparisons of religious exemption bills to racial segregation “mendacious and hysterical”) to well-meaning straights who support gay equality, like Saletan and the Atlantic’s Conor Friedersdorf (who defended the photographer’s discrimination as rooted in sincere “Christian beliefs”), to gay writers like Brandon Ambrosino (the most simpleminded instance of a gay apologia, in which the latest bête noire of gay advocates argued that “being against gay marriage doesn’t make you a homophobe” because—and this really was the crux of his argument—if it did, that would make his parents and the pope anti-gay, apparently not a notion the writer is able to entertain).

All these defenses of opposition to gay marriage may have had a certain validity to them once upon a time. But do they today? And if not, why are gay and progressive voices giving a pass to homophobia? I’ll focus here on Saletan’s argument that “opposing same-sex marriage is more defensible” than opposing interracial marriage and that, even though he disagrees with the anti-gay-marriage position, declares it’s not “irrational.”

Saletan’s reasoning is that religious arguments against interracial marriage were “objectively false” and there is “no biological basis” for them, whereas “a rational person can maintain that a relationship between two people categorically incapable of producing children together—that is, two people of the same sex—can’t be a marriage.” He further argues that the fact that “[m]arriage has historically been a sexual institution” can “justify a person’s refusal to accept a same-sex relationship as a marriage.”

In his post on whether fighting gay marriage makes you a bigot, Saletan claims a moral parity between “stereotyping and vilifying” gay marriage opponents and doing the same to gay people. “The rest of us need to broaden our experience,” he concludes, taking seriously those who simply believe, often citing their faith, that “marriage should be reserved for couples capable of procreation.”

These arguments are plagued by logical problems. Saletan acknowledges that upfront, but then he strangely ignores them all, which allows him to conclude that his distinction between racism and opposition to gay marriage is rational. For starters, I think it underappreciates how deep and sincere the racists’ beliefs that rationalized segregation were—thus giving a free pass to people today who use religious beliefs to support anti-gay stances. After all, the religious liberty argument is not that people’s beliefs are “objectively” true but that they are entitled to their beliefs irrespective of whether they’re true—that’s why it’s called “faith.”

Saletan’s other reasoning also falls flat. The fact that something has “historically” been defined in a particular way is not an argument that it should remain that way. If it is, slavery is just fine, and no change is ever good. As for the procreation argument, as Saletan allows, we let all kinds of people marry who can’t, won’t, or don’t procreate. A “biological” argument against gay marriage is no more rational today than it was when used against interracial marriage. That’s particularly the case today, because unlike 50 years ago, childless marriages, second marriages, step-parenting, and other non-procreative pairings are routinely accepted by religious people who continue to single out same-sex unions as uniquely disqualified.

Indeed, divorce and remarriage are strongly condemned in the New Testament (“Anyone who divorces his wife, except for sexual immorality, and marries another woman commits adultery”), but there is no serious movement today to ban divorced people from getting married—just gays. If Christian faith, and not problems with gayness, is really the reason you oppose gay marriage, you had better not have attended, served, or approved of a second marriage. If you have, as I suspect the vast majority of gay marriage opponents have, your opposition to gay marriage is highly suspect. (As part of Friedersdorf’s defense of the anti-gay photographer’s position, he mentions that she also declined to take pictures of nudity and violence, neither of which is expected at my gay wedding this fall. The divorce and remarriage question is the far better, and less insulting, test.)

The obvious hypocrisy of the religious freedom argument has for years prompted social conservatives to tie themselves in knots seeking a secular argument for blocking gay marriage, one that appears to be a rational concern about social harms rather than an article of religious faith. Their strongest arguments are still bunk. Yet though he disagrees with them, Saletan accepts as “rational” and “defensible” arguments by the virulently anti-gay conservative Catholic professor Robert George that, in Saletan’s paraphrase, “sex is a much brighter line than fertility or intention to bear children.” The “bright line” argument says that since what gender you are is literally easier to see than deeper and more important things like love, commitment, and responsibility, it’s a reasonable basis for doling out or withholding marriage rights. George actually argues that “an infertile man and woman can together still form a true marriage” while a gay couple can’t because “the behavioral part” of a straight sex act remains “ordered to reproduction even when nonbehavioral factors” like infertility don’t. Slate’s Mark Stern deftly dispatched this argument thusly: “In other words, you should copulate with your opposite-sex spouse not to make a baby, but to behave in a way that would make a baby if you were fertile. Coitus is sacred not as a means, but as a performance.”

Or as I’d put it: Sorry, gays, even though all kinds of straight unions are infertile, just like yours, you just look too different to play our reindeer games.

This is a terrible argument. But is it “irrational”—an important test that’s relevant not only to public debates but to the mounds of constitutional challenges to gay marriage bans? It’s true that not all bad arguments are irrational. Nobel Prize-winning psychologist Daniel Kahneman, perhaps the world’s leading authority on rational behavior theory, notes that rationality “is about logical coherence” and does not require being reasonable. “A rational person can believe in ghosts so long as all her other beliefs are consistent with the existence of ghosts,” he writes. The only test of rationality is whether a person’s beliefs and preferences are “internally consistent.”

That’s a very clear test, and anti-gay-marriage arguments clearly fail it. I have yet to meet a gay marriage opponent who seriously seeks to deprive, by law, a post-menopausal woman the right to marry, or a single person the right to parent, or a divorced person the right to re-marry. To be internally consistent—that is, “rational”—gay marriage opponents who base their position on religious faith or assertions that marriage is about procreation would have to oppose way more than gay marriage. I’m sure there are such cultural luddites out there, but I doubt this is the cohort Saletan is speaking about.

Even if it were, as a matter of law, courts are consistently finding that there is no rational basis for sexual orientation discrimination—including in marriage. The fact that divorce and second marriages are legal means that marriage is no longer what the Bible says it should be. That’s one reason that, in at least a dozen cases in the last nine months, every last one has been decided in favor of marriage equality. Part of Saletan’s hesitation in finding the anti-gay-marriage argument bigoted is his belief that there are rational, instead of emotional, arguments against it. If there is no rational argument against it, that position falls apart.

Let me grant that in one important way opposition to gay marriage is more forgivable than opposition to interracial marriage: Gay marriage is a more recent conceptual possibility because gay identity is a newer development than the construction of race. In a sense, since views on this issue have changed so rapidly, it seems only fair to, as Andrew Sullivan puts it, give people “space” to come along, or even to hold bigoted views in peace. But calling these views today “rational” or “defensible,” or saying they can be “accommodated in a decent society,” as Saletan does, is another matter. Moral positions evolve as new information and possibilities become available. And for all the incessant moralizing of the right wing over the last 50 years, the sin of current opponents of gay marriage is an unwillingness to open their minds to change. There comes a time when there’s only one morally correct answer, and the space for having the wrong answer has dried up. I’d argue that time has come.