What about aliens -- good or bad?

Proof of aliens with either no religion or religions different from ours would ultimately spell the end of our religions, except maybe those without deities and a philosophy.  Whether that would do good or harm is a different question, as so many are so dependent on their religious beliefs for their sense of purpose and future.

I'm not terribly concerned about an alien invasion, unless it turns out physics as we now know it is all wrong, which doesn't seem to be likely.  However, I wouldn't want to go off half-cocked building a contraption they send us instructions on how to build, as was done in some movies.

If we ever do meet face to face, the odds are significantly in favor of a peaceful, productive, and helpful relationship.