|Re Trumpty's lack of smarts:|
We know Tillerson called him a "f*&*&$% moron: and refuses to deny it or apologize for it.
We know Bannon says he's like an 11 yr child.
Now good friend Barrack says “He’s not only crazy, he’s stupid.”
Well, who is Thomas Barrack?
Thomas J. "Tom" Barrack Jr. (born 1947/1948) is an American private equity real estate investor and the founder, chairman, and CEOof Colony NorthStar. Barrack is a close friend and ally of President Donald Trump who has represented Trump on television news segments. He also served as the chairman of the Presidential Inaugural Committee.
Barrack endorsed Donald Trump for President of the United States in 2016.  He is a major fundraiser for Trump's campaign through the "Rebuilding America Now" Super PAC.   He spoke at the 2016 Republican National Convention. 
So Barrack knows Donnie well, has for decades. Is a conservative Republican. How you going to argue with that assessment?