Nobody can deny the fact that Christianity has played a huge role in our history. From the first Thanksgiving to the ideas of Jesus Christ that are embroidered in our culture today, Christianity and the Bible is responsible a big part of our heritage.
However, many conservatives will take this fact way out of context. They'll think that you have to be a Christian to be patriotic, which is simply not true. Following the more secular teachings of Jesus Christ (being charitable, loving one another, treating strangers with kindness) is what the men who founded this country were for.
I don't want to waste my time listing all these obscurant far-right arguments, so instead I'll list the facts straight from our forefathers.