I suspect few people are stepping back and looking at this from a point of view of abstract principles. Your response is unusual, and few liberals would have made it, or even understood why I asked the question.

Most liberals are for gay marriage because it's on the list of things they're supposed to be for, and like many other issues, they haven't thought it through at all. To be fair, a lot of conservatives do the same thing on their side.

For the record, I would have no problem with legal polygamy, but I would bet that almost every person who supports gay marriage would say that it should be illegal, although they have no logical rationale for why one arrangement is okay but another is not.

When you get down to it, the real problem is that marriage has become a government-driven issue. Like a lot of other things, maybe it shouldn't have been.