David thinks that establishing a two-marriage limit would “sociologically. . .be a much greater victory for marriage than maintaining whatever is left of the institution’s orientation towards complementary sexual union.”
I think it would indeed be a greater victory, but it is correspondingly less likely to gain support. You can get more people to agree that marriage is inherently heterosexual than to agree that the government should limit it. The thing is, I seriously doubt that we would have had the SSM movement in the first place if marriage culture were healthy enough for any such two-marriage rule to gain popular support. SSM seems to me merely the last stage in the destruction of traditional marriage, which is itself the main front in the attack on sexual ethics, simpliciter. I agree with Diogenes that SSM represents an attempt to definitively break the back of any sexual ethics irreducible to ordinary preference utilitarianism. He writes:
Imagine that the attitudes of a century ago — when marriage was accorded the power to ennoble sexual relations — could be beamed forward into the present. And imagine today’s parents of a young man betrothed to another young man, urging him to remain a virgin until his wedding so as to preserve intact his and his fiancé’s purity. Or imagine a same-sex couple, piously abstaining from fellatio or rimming during the season of Lent, only to resume it with prayerful joy on Easter morning. Simply to raise these possibilities is to see how grotesque they are. The decision to countenance same-sex unions is not to shift sodomy in one’s books from the “immoral” to the “moral” column, it is to dispense with the category of sexual morality full stop. It is to rip up one’s passport and renounce one’s citizenship in the commonwealth of sexual morality.
Gay activists taunt the rest of us that conventional man-woman marriage is in a shambles today, and they’re right. But their proposed innovation, as they really understand and rarely admit, is a choice for moral anarchy. Within their world there is no question of calling one act pure and another act impure, because the notion of purity has to be put to death before their project is embarked on. Chastity cannot be ennobling because to embrace same-sex congress is to debunk nobility. Even the photos from the Pride parades display a kind of sack-dance gloating over the dethronement of the concepts of purity and sexual integrity; it’s a burlesque of those values that marriage — real marriage — was ordained to uphold.
Same-sex marriage is a war on honor. And it appears to be winning.
This is not to say that some individuals may not be sincere in seeking an ennobled gay sex (so I won’t make Diogenes’ sweeping assertions about what activists “really understand and rarely admit”), but even casual inspection of mainstream gay literature reveals a subculture without so much as concepts roughly corresponding to ‘purity.’ I would be totally shocked if a sustainable splinter-subculture formed with a ‘virtually normal’ understanding of the proper use of human sexuality. Even the apostles (cf. Andrew Sullivan) of virtual normality sometimes say, sotto voce, that gay couples will teach heterosexuals to (for instance) lighten up on the whole sexual fidelity thing.