Just go onto any of the religious threads in the religion forum...there you will find many major disagreements going on, about just what the Bible is saying...for some churches, there may be small differences between them and other churches, but there are also many major differences that are argued about and discussed every day here on FR, in the religious forums...and they can get every bit as nasty as any of the CREVO threads get...the religion moderator works overtime, I do believe, keeping the posters in check...the religion moderator even has special rules for the religious threads, rules which are even stricter than on the other threads...take a look at those threads, you might be surprised at what you find there...
All the major Christian denominations agree on the nature of Jesus Christ and his mission and teaching, and all use basically the same Bible. Everything else in minor, although human beings do like to find trivia to argue over. The differences are chiefly about liturgy, church organization, and the like. The threat to our freedom today comes not from believing Christians, but from people who actively, belligerently attack those of Judeo-Christian faiths. I repeat: Christianity is the foundation of the Western culture which produced our free institutions and the science so beloved of some posters here.
There were no atheists, and only a handful of deists, among the Fouding Fathers, although they did adhere to several Christian denominations.