Mr Summers, About a week ago, Americans bombed over two hundred people to death, half of whom were women and children,  and there was hardly a whisper of outrage. You ask if Putin and Assad can't take responsibility, who will? 
Perhaps if the US wasn't arming Al Qaeda and other terrorist groups, the war would have been over years ago and hundreds of thousands of lives would not have been lost. 
It's a lot more complicated than you seem to think. Trump is certainly not the saviour as you try to portray him.