Pulling out of the deal is a smart tactical move to maximise "profit".
You guys need to see this in a broader sense.
Iran needs all the political goodwill it can muster from the Europeans, they need it to maintain their regime - you'll notice that the growing middle class and to some extent the rest of rural Iran has been trying to put in moderates into the ruling class, basically sending the message to take care of their own populace instead of warmongering in Yemen, Syria etc. There's war/economic/theological fatigue amongst the general populace, Iran today is not the Iran we once knew in the 80's or 90's.
The goodwill they are enjoying right now will evaporate if they take any steps towards building any nukes, and regime change by Iranians tired of hardships would be a possibility. Trump is likely to know this and is applying appropriate pressure to make changes in the approaches the regimes takes. So nukes is out of the equation.
What Trump is trying to do is basically forcing the regime to survive, and to do that all they need to do is stop sponsoring terrorism in other countries. And why is that bad?
I think Trump is one smart motherfvcker