Oi! There are and always will be many other religions aside from Christianity. There's so much wrong with implying America is a Christian Nation, kind of assumes that everyone is Christian, everyone is not and never has been. The only reason America was "once" all Christian was through persecution of minorities so people kind of had to be "all Christian" or else.
Now they don't do it as much anymore even though some of them are still a$$holes but still, the only reason America ever was Christian was through force, the only way America would be any other religion aside from Christianity is through force because the reality is that we are diverse and we were never one religion to begin with.
Ug. End of.