Also note, this is not something I want.. But I am seeing a LOT of hate towards Muslims, and I don't think it would take much to have a lot support from Christians to either export them, or have them killed off.
Remember how powerful the political tools of religion and the media are in the USA.
Couple that to a deliberately undereducated general population and the will of the political leadership and it could be achieved in a very short period of time.