At a wide-ranging Monitor Breakfast meeting with reporters, Bob Corker, the ranking senator on the Foreign Relations Committee, also voiced concern over Russia and Ukraine.
And the ongoing refusal to recognize that pretending the US doesn't have limits to its power doesn't make it so.
Iran has assured skeptical diplomats that it is slowing its nuclear work. The latest report from the UN nuclear agency backs them up.
The US and Iran have attacked each other in public to sell nuclear talks to skeptical audiences at home. But harsh words have eroded trust.