I’m certainly not disagreeing that he’s sick in the head! 
However at the risk of nit-picking and over-explaining, psychiatric derailment is actually way worse than what Trump shows. His speech patterns make excessive use of unnecessary parantheticals; sentences like “this governor next to me is from South Beach – I’ve sold a lot of properties in South Beach over the years, believe me! – and he’s now going to say a few words about how awesome I am”. It’s an unnecessary spin-off from the key subject, and listening to him speak for an hour will make anyone dizzy, but his digressions are related to each other. They’re more a product of his poor impulse control than anything else. Actual psychiatric derailment involves leaving one train of thought behind and starting an unrelated one part way through – “this governor next to me is from South Beach – chocolate chip cookies are better than oatmeal cookies, because… you know my favorite shoes are blue”. It’s total chaos; one typically sees it with schizophrenics.
I don’t need a name for his condition. I just know Trump is nuts. Get rid of him.
“I frankly don’t expect him to hold to a position for more than a few minutes, let alone an entire day,” Coons told CNN’s John Berman.
Unlike Coons’ buddy Jeff Flake, who can hold to a principled position for just under a week.
breaking news … this is the same mild-mannered fella who said that Trump’s move from concrete to steel was a meaningful concession and important “progress” : “I hope the president will hold to that position, because that is a minor but important difference in technology. A fourth-century concrete wall that you can’t see through will be a less effective border barrier.”
He’s so bubble-brained.
There’s no point in discussing anything with him.
Democrats should just ignore Trump and speak to (and about) Mitch McConnell. Put the pressure on him to reopen the government. He is the responsible adult in charge here.