The $400 million was IRANIAN money that the U.S. had frozen as part of sanctions against Iran dating back to 1979. We simply gave their own money back to them. But I suspect you knew that, and you're just intentionally being intellectually-dishonest and obtuse by misconstruing the payment as being American taxpayer dollars. Par for the course for you, though.
http://fortune.com/2016/08/05/money-america-iran/
But anyways, good job quibbling over the fact that this deal is not a treaty, which literally no one claimed it was. I guess that's easier than you actually offering an honest opinion about Trump's warmongering against Iran. When you can't bring yourself to offer a critical opinion about Trump's policies, just default to criticizing Obama and Hillary Clinton.
Meanwhile, Israel just "pre-emptively" bombed Iranian troops in Syria again for the second time in two weeks, while also calling up reservists and deploying air defense systems to the Golan Heights. And Rudy Giuliani just said three days ago that Trump remains committed to "regime change" in Iran. It looks like John Bolton may get an early Christmas gift this year.