FYI: I'm an athiest, but I still like Christmas trees, I like seeing creches in front yards, I have no problem with prayer and I like it that there are so many people who are devout in their faith, regardless of their faith.
I have no problem with Christmas plays in public schools, or Christmas trees or kids exchanging presents ... it is a large part of our heritage. I do have an issue with school sponsored prayers, but I don't have an issue with politicians leading others in prayer in Congress.
We are most definitely not a Christian nation, but we are a nation populated by a majority of people who identify with Christianity. Christians, who by the way, wrote the Constitution to be all-inclusive and accepting of all faiths and those who choose not to believe.
I will not debate any apparent inconsistency in anything I've said here because I don't see that it is important. I like the season. Merry Christmas.