“Since Maggie Gallagher and other experts have clearly identified the benefits that marriage provides children, the children of same-sex couples are being treated as a disfavored group, legally.”

How does marriage benefit children? The answer is not that marriage confers general respectability or practical benefits. If that were true, then children in remarried families would do better than children with unmarried parents. And they don’t, on average.

Marriage benefits children to the extent that it keeps the child’s own mother and father in a permanent, not-too-high-conflict union.

But here’s the interesting thing. Back in the 1990s, when I went into the public square and said, “Marriage really matters because children need a mom and a dad,” I wasn’t permitted to rest my case on vague generalities — I was required to produce data. Mounds of data, in fact. We have no scientific evidence at all, that I know of, that children raised by same-sex couples benefit if their unions are legally considered marriages.

Why is that now self-evident? Why is no data at all required of people proposing novel family forms, while anyone advocating for something traditional requires mounds of scientific data to get a hearing in the public square? Stacey and Biblarz have published a new study (I have only scanned it), but one big fact leaps out: They concede, as the Prop 8 expert witness conceded, we have no scientific information at all on how children fare in motherless families. But that doesn’t seem to matter, does it?

I do not think same-sex marriage will serve child well-being in any appreciable way, and I don’t think there is much sign that that is the goal. The gay community is by and large supporting same-sex marriage as a right, not as a norm at all. Relatively few same-sex couples enter same-sex marriages and the dissolution rates (at least in Sweden, where we have hard data) are extraordinarily high (roughly 50 percent higher for gay men, 100 percent higher for lesbian couples).

Same-sex marriage is primarily an attempt to serve the dignity interests of gay people. It represents the government’s good housekeeping seal of approval on the idea that their relationships are the same as anyone else. Let’s not fool ourselves; we’re not doing this for the kids.