For anyone who opposes SSM (and ENDA) this is really the only position you can have. Once you agree that being gay isn't a choice, there is no longer any rationale for opposition to gay rights. So opponents have to be in the choice crowd (like Santorum or Carson) or "I dont know." At least there is some consistency. Rubio tried for moderate heroism by saying being gay isn't a choice, but gays still shouldnt be allowed to get married. In my book that is worse.
It's a choice.. Plain and simple.
OK, I'll bite. How do you know this?