Recently there's been a flurry of public discussion centered around the bogus idea that the USA was supposed to be a "Christian nation". The secular humanists at Talk to Action have put up a number of stories about it which I'll link here:
Michael Medved Yearns for the Good Old Days of 1817 (or better yet, 1620)
Rush Limbaugh's Historical Ignorance
United States Treaties with the Barbary States pt.1 pt.2 pt.3
Is America a Christian Nation?
Oh, how I wish more people would make the distinction between the necessity of religion for a healthy society or the desirability of a religious or even Christian society; and an explicitly "Christian" government.