Why are some people so threatened by Creationism?

I'm not threatened by it on its own, but as part of an agenda that leads to the U.S. instituting Christianity as a state religion it becomes a scary thing indeed. If you wish to teach creationism AT ALL it must be in a religious context, because IT IS NOT SCIENCE, and teaching in a religious context doesn't belong in a public school but in church. This is the "teach the controversy" argument. Only problem is, there is no controversy. Creation theory is devoid of ANY verifiable, empirical and peer-reviewed evidence to support it. It is solely faith-based.