Trust them as to what?
Trust them not to develop a nuclear capability as the US, the UK, France, Israel, and India all have
No I think they're doing that
Trust them not to fly half way aroundthe world and invade another country like we and the US have - Yep I think e can trust them not to do that.
You need to look at things from their perspective. Western countries have had a habit of enforcing their will in the middle East backed up by military force - the one thing that keeps them out is the threat of a nuclear response - see Korea
If I were running Iran - I'd be refining Uranium too!