There's no reason for them to even be after him other than greed, using justice as an excuse.
If a non-aggressive god-like superpower pops up in your backyard the #1 thing you should do is make friends as fast as possible. Especially since you can't fuckin' do a thing to them. Do they think they can probe him by sending an army after him to kill him, and when he destroys that, THEN try to sue for peace? Because that'd only work on this guy.
That said, despite him being incredibly kind and passive, y'all need to chill on this. Yes, he knows he's strong, he's scared of his own power because he doesn't want to hurt anyone or accidentally destroy the planet. He'd much rather be a happy tourist, make friends, and never have to do so much as flex. Just because all of you think YOU'D be some macho murder machine with his level of strength (you'd be a psychopath if you actually would) doesn't mean he has to be, or that he's a bitch wuss for not doing so.
No, if anything, these girls are the wusses for letting Nash talk like that and touch them in such a way. Is there nothing to punish sexual harassment? Are they not allowed to kick his ass? Are they willing to fight and die for a country that allows someone like Nash to call their heroes cum dumpsters without being decimated for it?