Sanctions on Iran, to halt production of weapons grade uranium, would have failed without the cooperation of both Russia and China. There was no way that either Russia or China would have moved the goal posts to include stopping aid to Assad of Syria (a declared ally of Russia) or to freeing U.S. citizens from foreign jails (both Russia and China have incarcerated our citizens).
I don't recall, ever, that any other American President was excoriated for what was not accomplished by a treaty without any praise for what was accomplished. Nixon reached detente with Red China without reforming the political system of that nation or eliciting a pledge to stop supporting rogue states like North Korea? No calls were issued to go back to the cold war. Reagan reached nuclear treaties with the Soviet Union without extraneous demands? No criticism was leveled that the treaty should not be signed because what was accomplished in arms reductions didn't go far enough or that political prisoners were not released from the Gulag.
While other Presidents have been judged by ability to achieve what was possible, our current President earns praise only if he does the impossible.