I don't think that's really manifest destiny. But sure, I've heard the stuff about dominion over the Earth. It's bad Christian theology in addition to being bad politics. That Man is to have dominion over the Earth does not imply that there's nothing he can do to make it worse for himself and his fellows. But I'm often surprised at how little many Christians I meet seem to know about the Bible or Christian theology. I guess it's mostly a cultural affiliation for many people.