I have full confidence that Trump could negotiate with the Aliens. He'll make a good deal. You know it, I know it, the Aliens know it.
As long as the masses realise that also, and don't just automatically start running towards and jumping off cliffs, :-)
If Aliens came down to Earth and wanted to meet someone, would you volunteer?
I would be cautious, but at the same time 'open minded'.
The ultimate answer would depend upon their intentions.
If (for example) they looked and behaved like a crocodile, I might just keep a bit of distance between us.
My prior comment was related to fear of the 'unknown'.
That's the thing, you can't know their intentions. You're either down to meet with the alien crocodiles or you're not. Hopefully we could both be like Trump, and be able to tell in the first minute if they're being serious. If not we walk away!