Since the debate over whether gays & lesbians have a "right" to marriage started brewing several years ago, my thoughts on the matter took time to coalesce. But coalesce they did and here's what I came up with:
Marriage is a legal arrangement between parties that have attendant legal rights; the ability to take title to property as "tenants by the entirety," is one small example and the one with which I am most familiar.
State legislatures have the authority to define legal arrangements in their respective states. Other states, under Article IV (full faith and credit clause) must abide by these arrangements unless otherwise proscribed by congress. Which congress took care of with the absurdly named "Defense of Marriage Act." I think the name foolish, but the authority of the congress to do this is without question. So it was fine to me the way things were going. And I thought a constitutional amendment trying to define marriage was/is an asinine idea.
The libertarian in me doesn't care about who wants to marry whom, but the small conservative in me (getting smaller by the day) prefers that the arrangement be handled by the state legislatures. I didn't think this an area where judges have the authority to decide that now things are different, and we now think that marriage can be between people of the same gender.
The past tense in that last sentence probably gave me away.
I was in traffic tonight pondering this (there was a news update on NPR about the California Supreme Court hearing challenges to the recently passed Proposition 8). I was going through in my head, again, that the states are well within their rights to decide who can engage with whom in certain contracts when it hit me.
No, they can't.
The Commonwealth of Pennsylvania (for example only) can corporately dislike gay people and gay lifestyles and everything else gay. But the Commonwealth of Pennsylvania has certain rules set-up affecting the establishment of corporations/partnerships/legal arrangements. If two or more people join together to form a Limited Liability Company or a Corporation, following the proper guidelines established by the legislature (a legitimate, if overwrought, use of government authority) no state or commonwealth can proscribe a particular class of citizens (however defined) from assembly--not including criminals (it seems reasonable to me to prevent certain types of convicted felons from participating in certain activities).
In other words, if the people of Pennsylvania tried to say, via legislation, that gays could not form a General Partnership, the legislation would be promptly (& rightly) rent asunder by any court worthy of the name. The same holds true for licensing authority. There is no compelling reason for the state to deny a gay person a driver's license, an insurance license or a license to do any of the other things that the state in it's infinite wisdom deem requisite of licensing.
The argument that "marriage is different" fails in that the same argument could have been made to justify and perpetuate any social change that is now taken for granted that wasn't explicitly sanctioned by legislature. For example, women were able to own, purchase and transfer property without express statutory authorization. Cultural norms, of which I'm typically a fan, slowly evolved from only white, Christian men being allowed to take title to everyone being able to, regardless of gender, creed, race or sexual orientation. It fails the reasonableness test to claim that gays can participate in every other form of legal contract, save this one. You know, because they'd ruin it.
If marriage (or our culture) can't withstand the "assault" of gays wanting to be married, then what good is it?
None of the above changes the fact that this is still entirely a state issue and of no concern of the federal government in any context.