That's hard to believe gays would be that dumb but of course I take your word for it. I've had similar conversations with liberals. I'll mention that the Islamic fascists hate gays and women, and they'll reply that our "Christian Dominionists" do as well. (A Dominionist of course is someone who believes in a Biblical theocracy; liberals think this describes all conservative Christians.) I'll mention that Iran (which is the usual focus of the conversation) executes gays, and they'll reply that gays get killed in the US. The notion seems to be lost on them that in one case it's the state performing judicial murder, and in the other, it's individuals breaking the law. Or they'll claim that the Christians want to kill the gays here but don't have power yet. It's like arguing with someone in an cult.
There are a few gays that get it. I did a double-take a couple of years ago when I saw the book While Europe Slept, by Bruce Bawer. He is a gay liberal whose earlier book Stealing Jesus claimed that fundamentalists were wrong on the Bible and gays. In his new book, he describes how serious the danger is from Islamic fascism in Europe. Apparently he and his lover moved over there, expecting a liberal paradise, and found something entirely different.