in regard to this thread, you guys might be familiar with the documentary entitled
"Ancient Aliens" which aired on the History Channel a while back...
Well, if you are or aren't familiar with it, there is now a series based off of it called "Ancient Aliens" which talks about all the possibilities of Aliens interacting with, and even assisting humanity with technological feats and advancements throughout history.
new episodes of the show air every Tuesday night, (if you're in the US) at 8PM (7PM central time)
Also, if Aliens have interacted with us in the past, and they're responsible for some of our technological advances, who's to say they'll try to destroy us if we encounter them again?
if anything, I think humanity would try to destroy them, and then they'd be like "NO U" and vaporize our planet, but if we didn't try to destroy them, maybe there could be coexistence of some kind.