You suggest that perhaps the state should get out of the marrying business altogether.
I guess the first thing to say is that they can't do it in a way that just simply takes away the possibility of marriage from gays and lesbians. During integration in the South there were attempts to get around mandatory integration by ending the program in question. They closed down the public swimming pools or the public schools rather than integrate them. That kind of thing has been held to be unconstitutional, and quite rightly so. But I guess I think that marriage as it currently exists is a weird institution. There are a bunch of civil benefits that could be captured in civil unions. There are religious elements, but they're not really part of state marriage. Then there's the expressive significance–we want the state to dignify or affirm our marriage. Should the state be in the business of dignifying certain unions? The answer would be no. If we were starting over again, we'd want to go back and look at the privileges associated with marriage–tax benefits, immigration status, etc.– and ask, Who do we want to give those benefits to? What do we want to do? That kind of thorough rethinking would be ideal, but it's also not likely to actually happen. How do we get from where we are to there? In the short run, I think the best thing is just to push on the equality issue and say, So long as marriage is offered by the state, it should be offered with an even hand.