This isn't about voicing your religious opinions (both theists and atheists do this) - this is about enacting and enforcing laws based on a set of religious opinions you feel are somehow superior to that of any other (theists do this). Can you really not differentiate between wanting to be free of oppression and wanting to oppress? You have every right to tell me you think my opinion is total shit. You do not, however, have any right to stop me just because you think its shit. As an American, this basic fundemental idea is the very core of my existence. The only legislation on the matter that matters to an atheist is that there be no fucking legislation on matter. So where's the logic behind the theist demand for power over atheists? That they are persecuted if they aren't given the right to persecute? That atheists want to oppress them? That somehow their lives are negatively affected by atheists being atheists? That's the difference.

Lets say your neighbors John and Jim are atheists who want to get married.

Atheist response: "You're getting married? Good for you. I hope you shut the blinds when you fuck, though. I don't need to see that nasty shit." * - insulting but minding your own business.*

Theist response: "You and your sinner friends want to destroy marriage, turn our children gay, and force us all to have a big gay orgy down at Big Gay Al's Big Gay Emporium! And possibly make it legal to fuck a billy goat. ZOMG, if my children become aware that homosexuality is a thing, they're gonna go gay. Or fuck a billy goat! You must be stopped!" - insulting and minding someone else's business.

Now that's just one example issue but it applies universally. If you can't see how speech alone ("You're a moron!") differs from action (I hate morons. You're not allowed to exist!"), I suggest a CAT scan.