Meh. I'm not so concerned with trashing the Iran deal. As far as I can tell, Potus's hard stance against Iran is about posturing for an acceptable peace in Syria, where the US can back out and save some face.
It's also to placate Greatest Ally, who want us to go to war with Iran/Syria/Russia - thus scraping the deal is a step in that direction as far as I can tell.
I do agree that Merkel is terrible though.