would destroy us if they could. they'd show that they are superior to us. I believe in it. but they're not friendly.
Why does another life form have to be murderous?
You hear the same thing about AI - "it will kill us all".
Testosterone is what makes humans aggressive. We don't know if aliens will have it, and we know AI won't.

I think we need to believe in aliens because there is a lot of planets like earth and now a days astronauts says on some planet there is all chances for human to live there and they also says that water weather all the things are present there so I also think aliens will exists.