In many ways I'm as mainstream as they come. When it comes to religion, I'm a struggling but committed member of a mainline (liberal) Protestant church, and am raising my son in that faith. (He's free to reject that faith when he's older, but I want to be sure that he starts with a moral foundation in life so he'll have a basis of comparison. I think it's important for a child to grow up rooted rather than rootless, so I'm starting with The Universe As I Understand It.) I have quite a few friends -- my two closest friends, in fact -- who don't agree. One's nonspecifically spiritual, the other atheist. Somehow, we all get along. Somehow, we look at each other as equally worthwhile and a part of the great American society.
Supreme Court Justice Antonin Scalia seems to disagree: "[I]t is entirely clear from our Nation's historical practices that the Establishment Clause permits this disregard of polytheists and believers in unconcerned deities, just as it permits the disregard of devout atheists."
I really ought to read his whole dissent, but I'm not sure I could stomach it.