From whence gay marriage?

There's a somewhat interesting article at Public Discourse questioning where the demand for gay marriage comes from. The thesis is basically that gay marriage wasn't an issue a few decades ago -- even advocates of gay rights didn't bring it up (for the sake of argument, I'll take his word on this). So the author wonders why this demand gained popularity so suddenly (and whether that speed is healthy). While I'm not an expert, I will propose an explanation for the suddenness of the transformation. Basically, I believe that the historic prosecution of homosexuality kept the idea of marriage off the radar. For heterosexuals, they never thought about it because they didn't know any open homosexuals and were unaware that anyone would care about homosexual marriage. For people with homosexual tendencies, they could not establish stable long term homosexual relationships (due to persecution), so it never really occurred to them what benefits could come from formal recognition. During this period, gays were by definition embracing an alternative lifestyle, which in turn influenced their views on traditional institutions such as marriage. Now that homosexual relationships are mainstream, the consequences of marriage discrimination are apparent and homosexual marriage has been embraced as a natural component of mainstream acceptance of homosexual relationships.

Aside from offering that theory, I want to quickly dismiss the authors assertion of the conjugal theory of marriage. He writes:

but they marry in order to make something new that honors and ennobles that attraction and love: the nucleus of a family, in a comprehensive relation of husband and wife that points toward the future, with an openness toward making that future through procreation.

From what I've seen and read, this is not the current mainstream attitude towards marriage. Instead, marriage is an expression of romantic love and commitment. What I learned in history class is that this romantic theory of marriage gained prominence in the 1950s and was largely the norm by the late 1970s (at least among the college-educated middle-class). Within this context, childbearing is an exciting opportunity offered by marriage, but definitely not the point of marriage.

To say that there is no reason for formal recognition of the household in the absence of childbearing is silly (and I won't give any attention to semantic quibbles over the word "marriage"). We have standard legal recognition of many arrangements, including business partnerships and corporations. Why not a household? Why not give a special place to a union of two adults. And no, the recognition of gay marriage does not imply that we should also recognize threesomes -- there is a major, consequence of the union of two people which is not comparable to the effect of adding a third*.

Anyway, it's not all that surprising that gay marriage has suddenly become an issue, and it's not all that radical given the preceding changes to our conception of marriage and the mainstreaming of homosexual relationships. In many ways, it is just the cherry on top.

*Okay, upon more thought, maybe my logic would allow for the recognition of threesomes (but not larger groups). The problem with recognition of pairs only is that if a threesome were to form, then one member would not have any recognition of his relationship.