Consider this piece from the first century BCE poet Catullus (Carmen 61:134-141), in which the poet addresses himself to a bridegroom on the eve of his nuptials:
"You are said to find it hard, Perfumed bridegroom, to give up Smooth-skinned boys, but give them up... We realize you've only known Permitted pleasures: husbands, though, Have no right to the same pleasures."
The social history behind this piece is clear: once they've experienced sex with other men, Catullus tells us, men are unsatisfied with what their new wives provide them. Notice that the poet is unconcerned about the husband's dallying with other women -- it's the other men around that threaten the marital union.
Okay, let's see if you can follow this. If men are allowed to marry other men, women will lose out because because they when marry men---which at leas Klinghoffer will concede will still be legal---they will not be able to keep their marriages together because once a guy has tasted forbidden man flesh, he can't go back to inadequate lady flesh. Men can step out with other women without threatening the main marriage, because apparently it's just easier for men to close their eyes and imagine that the missus is the mistress long enough to complete his conjugal duties. So if gay marriage is legalized, all the men will want to fuck each other, and women will have no one decent to marry. Women can't marry each other, of course, because a) Klinghoffer keeps forgetting about lesbians when he's dwelling on the delicious images of an ancient Roman cornucopia of manflesh and b) just like men, women can't lower themselves to touching women once they've sampled the dudely goods.
Let's face it. No one wants vagina when penis is available, end of story. You, like Klinghoffer, know that if you ever succumb even once to the urge to reach out and touch a cock, you will forever be ruined, never able again to muster enough pleasure out of a union with a lady to get through it.
But what I find really interesting about Klinghoffer's argument is this---he's trying to argue against gay marriage. Like many panicked wingnuts, he seems to think that legalizing gay marriage=legalizing dudes fucking each other. What they fail to understand is that dudes can already legally fuck each other. Though perhaps they have to mentally block this knowledge lest they give into the urge that they claim that all straight men have, to drop their wives and run off to swim in a sea of testicles. But the truth is that Klinghoffer's fears are already being tested in the real world. Plain old back hair-sporting straight husbands everywhere can, if they want to, go off and suck all the cock that they want. Even the risotto-making husbands, or in the wingnut imagination, especially the risotto-making husbands. We already have the built-in all-purpose dudely excuse---sports. You and your guy friends are going off to watch a game, you tell your wife, not letting her know that actually you and your friends have a standing Monday night orgy. And when your interest in sex with her grinds to a halt because she can't compare to the exquisite man flesh, she'll write it off as the sad result of too much time spent over risotto.
This scenario is already 100% legal, as long as the orgy is conducted on private property and doesn't disturb the neighbors. Gay marriage doesn't make this more or less legal. So, assuming that men have permission to have sex with other men. Klinghoffer perhaps means that if men have an chance to marry other men, they won't marry women. That's certainly what he hints at here:
The losers from all this will be the vast majority of women. With full social sanction given to homoerotic activity, the historical precedent suggests that tomorrow's women will have a harder time finding and holding on to suitable men. As women will suffer, so will the vitality and stability of the nuclear family.
But he doesn't actually say this. He just says that once you've gone dude, you can't find the inadequate female body arousing any longer, which means that marriages will fall apart due to lack of sex. That full social sanction of homoerotic activity is all it takes. Which is a clever, slippery way to avoid the fact that actually, for the purposes of his argument, we already have that. Men can have sex with men without being punished for it, so why aren't straight men---who all secretly would prefer to fuck dudes---not taking advantage?