Poor Iran. They had it really good when the Obama Administration was having John Kerry act as their lawyer, even though we were supposedly engaged in tough-as-nails negotiations with them. They were good times for the mad mullahs. Every time they wanted one, Kerry would give them two. Then when other nations would object to Iran's terms, Kerry would run interference for Iran so they didn't have to do it for themselves.
Support of terrorism? Why let a little thing like that scuttle a perfectly terrible nuclear deal? The use of unfrozen assets to finance said terrorism? Hey! It's their money. Whaddayagunnado?
That was the stance of the Obama Administration because it was determined to get a deal, any deal, no matter how bad - just so they could say they got a deal. And that's exactly what they did. Now we live in a world where it's easier than before for Iran to become a nuclear power because our enforcement mechanisms are a joke and we've freed up the money they need to pay for the materials.