Intelligence chiefs have testified in front of congress that Iran was following through with it's end of the deal. The US then unilaterally decided to tear up the treaty and put in economic sanctions based on nothing. It's almost as if they want Iran to build nuclear weapons. It's also putting pressure on Europe to pull out of banking and business ties that were built after the embargoes were ended.
https://www.nytimes.com/2019/01/29/us/politics/kim-jong-trum...