People make the argument arguing for gay rights that homosexuality isn't a choice. There are some clever ways to address this point including asking heterosexuals: when did you choose to be straight. There is solid logic in that argument that no heterosexual choose to be straight then it follows that homosexuals probably aren't choosing that either. But the question of whether or not homosexuality is a choice is as simple (it isn't) as it is useless.
The is a simple way to show it is the wrong question and it is by asking this question: is pedophilia or attraction to children sexually a choice. I don't care whether or not that is a choice because sexually molesting a child is morally abhorrent. So the question about homosexuality really should be: 'do we find homosexuality to be morally abhorrent'.
If you base all of your morality from religious texts written greater than 1500 years ago then you are inclined to think of homosexuality as immoral or as an 'abomination'. I've written previously that not everyone who believes this is a bigot (although many bigots pretend to be christian to avoid having to own up to bigotry).
What if you don't get all of your moral views from Church on Sunday? What if you try and come up with your own moral understanding of the world? Other than quoting scripture I've never found a logical explanation for why two people loving each other and having a life together is a beautiful and wonderful thing except if they happen to have the same genitalia (and then it's an abomination).
Conservatives are right to denounce the collapse of the family unit over the last 100 years. The percentage of children born out of wedlock is discouraging. But scape goating gays for the lack of a coherent family unit (which is often brought on by absentee fathers) borders on the delusional.
The real question comes down to liberty. Should two consenting adults be able to enter into a legally binding contract (marriage) with each other so long as it doesn't harm anyone else. The liberty loving answer says yes, people should have the freedom to do things, even stupid things (like smoke). Republicans that seek to minimize gay freedoms and rights do so by attacking liberty and freedom, things conservatism is suppose to stand for. We ought to be standing for freedom and we ought to be reflecting on these moral questions.
So let's ask ourselves again: is homosexuality a choice? No. Would it matter if it were? No