Trump cancelled the deal. With no deal, there is no longer any reason for them to follow the agreements. Trump bombed iran for the same reason previous presidents have messed with it; Iran was attempting to subvert the american petrodollar, in this case by trading with china in chinese currency as opposed to USD, which would have prevented us from being able to sieze, tax, track or sanction it as it passes through US banks, and threaten the USD as the global reserve currency.