David Bass’ post yesterday on the David Blankenhorn/Maggie Gallagher business reminded me that I had wanted to respond to a comment on my own blog entry:

No law can force people to raise their kids, or be a responsible, engaged parent, or a good husband or wife. Whether gay people can or can not wed has no effect on whether heterosexual people will assume responsibility for the offspring they bring into this world. Don’t try to pawn off heterosexual parents making bad choices as somehow being the fault of the gays.

The first sentence of this comment is indisputably true. But the point isn’t to have laws that force potential parents or spouses to behave a certain way. It is to build institutions with incentives, norms, and customs that make them most likely to behave in that way. How do we define marriage as an institution and what do we expect of people who enter into it?

The problem isn’t “the gays.” The problem is what happens when you rewrite the basic rules and assumptions of marriage. Marriage cannot be government-recognized couplehood for some people and about procreation for other people. The ideal of traditional marriage is a public promise by two people to take care of each other and any children that their sexual union produces. A unisex definition of marriage is only compatible with the first half of that promise. A same-sex couple with children is missing one of the biological parents by design.

Thus if we believe “gay people can… wed,” then how can we also believe marriage is about ensuring that “heterosexual people will assume responsibility for the offspring they bring into this world”? The issue isn’t gay people somehow tempting heterosexual parents into abandoning their children, but whether the legal definition of marriage actually demands parents take care of their children. The rules will be re-written for everybody.

Reduced to legal couplehood, maybe marriage can still do for heterosexuals what it was intended to do. After all, there are many more heterosexuals than homosexuals. The data show that when same-sex marriage becomes law, only a minority of gays and lesbian couples actually get married. So marriage will remain an overwhelmingly heterosexual institution whether our marriage laws look like Mississippi’s or Massachusetts’.

David Blankenhorn certainly hopes so. He also hopes supporters of same-sex marriage will assent to the following propositions:

[O]nce we accept gay marriage, might we also agree that marrying before having children is a vital cultural value that all of us should do more to embrace? Can we agree that, for all lovers who want their love to last, marriage is preferable to cohabitation? Can we discuss whether both gays and straight people should think twice before denying children born through artificial reproductive technology the right to know and be known by their biological parents?

I don’t know what the answers to these questions will be, but I’m skeptical they will be the answers Blankenhorn is hoping for. But if it comes to pass, we’ll all have to hope so.