The gay-marriage debate is a baffling spectacle because, once you have abandoned the premise that homosexuality is evil and must be stigmatized, any remaining justification collapses. And yet a hardy, dwindling cohort of social conservatives soldier on nonetheless. Ross Douthat today argues that gay marriage is problematic because children raised by married, biological, opposite-sex parents fare better than other children. His conclusion seems highly disputable for reasons he himself mentions (the data set is entirely from the pre-gay marriage era, when gay parents were unmarried, closeted, and so on.) But the larger flaw here is that his entire focus on child welfare seems completely beside the point.
Regnerus’s study is a reminder of why marriage has traditionally been regarded as something other than just a celebration of love and a signifier of civic equality, and why the rationale for the institution has involved a child’s rights to his or her biological parents as well as in two lovers’ rights to one another.
Who is challenging "a child’s rights to his or her biological parents"? If gay marriage means my kids are going to be snatched away and raised by a pair of guys living near Dupont Circle, then I'm against it. But I'm pretty sure that's not part of gay marriage.
Indeed, there's nothing about gay marriage that is going to reduce the supply of children raised by married, opposite-sex biological parents. So even if we accept Douthat's highly dubious reading of the data, and we thus assume that it's vastly better for children to be raised by their married mommy and daddy, why does this argue in any way against gay marriage? Gays can acquire children through adoption, or through surrogate motherhood. None of these ways deprives a child of married, opposite-sex biological parenting. The only alternatives for such a baby are either not to be adopted or not to be born at all.
As for adoption, if you want to stretch Douthat's argument farther and assume the superiority of non-biological opposite sex parenting over gay parenting, then you could find a way to give opposite-sex couples adoption preference over gay couples without denying gays the right to marry. As for the latter, I assume an ardent pro-lifer like Douthat would concede that a baby is better off being raised by gays than not being born at all. Either way, the alleged superiority of straight, biological, married parenting to gay parenting is completely beside the point.