They imposed??? They didn't impose anything. It's not as though they're forcing people to go out and get married to someone of their own gender
What it says is that two people have equal protection and equal rights when they get married - be it a man and a woman, two men or two women. Really - in all seriousness - why is it even a question? If you (general you) believe it is wrong - don't do it. But who cares what other people do?
My friends have married some people I think are utter asses and totally wrong for them. Because I think that, should I have the right to say they can't get married? Of course not, it would be utterly ludicrous. Same principle really.
(PS - And no need for anyone to pull out the bible for me - I'm a born and raised Catholic who attended Catholic school. For every bible quote you pull out, I can pull out equally as many. But I think the wise Jeb Bartlett says it better than I ever could:
http://www.youtube.com/watch?v=rHaVUjjH3EI)