Lots of commentary on the Supreme Court's Ten Commandments decisions. I won't go there directly but will instead pick up from a line in George Will's column this morning--observing that Quaker, Anglican, Methodist and Baptist clergymen officiated (where, he's not clear--it may have been over Congress, or just over religious ceremonies held in the Capitol in the early 1800's).
I think we have always had a four-way divide: first there's the one true religion (which is the one I believe); second there are other religions believed by people who are good at heart, even though misguided in views on theology, organization, or other points of religious belief; third are the unbelievers, those who don't believe; and finally the believers in false religions.
Over the years Americans have come to include more and more religions/denominations/sects in the second category. It shows when we have public ceremonies, like inaugurations or funerals of bigshots or the services after 9/11. It does vary by time--Catholicism was a false religion, the whore of Babylon for the Puritans, got acceptable in the revolution, then lost that status as Catholic immigrants came in during the 19th century, and finally regained it by 1960 with JFK. Jews have made it into the other category, but Islam hasn't (witness Franklin Graham) quite yet. But we're getting close to the point where people say "we all worship the same God" (even though named Jehovah or Allah).
That leaves out the non-monotheistic religions. Will we say: "many paths to enlightenment" as the new euphemism? When will we have a Wiccan officiate at some national ceremony? (I suspect the rule is you have to have 2 percent or more of the electorate to qualify. But that should mean that Mormons are overdue for representation.)
As for the third category--unbelievers--I think some people, like Madalyn Murray O'Hair or Robert Ingersoll (famous agnostic circa 1890) probably are seen more as category 4, but many people tolerate them. Not that any representative of unbelief will ever appear on a national stage.