Real simple, Barney style just for you...
It's not about what Joe set out to do, it's about how badly he did it and the results obtained.
No one here is arguing that we should have stayed there. Keep beating that dead horse if it makes you feel better about things.
The plan and international agreement was May 1. Joe didn't like that because it was Trump's plan. So, Joe made his own plan. This is what happened. It ain't over yet. It'll get worse before it gets better.