If was walking around in a crowded place and just said the word "Christian" loudly, other than people looking at your weird for talking to yourself, I would not feel the least bit uncomfortable. I'd feel no different than if I said "Train." Can't say the same thing for "Jew"
well i think that gets more to the persecution angle and that you're a wasp. would you just be like "blacks" or "gays" even though those aren't considered to be demeaning labels?