Harry Truman was clearly mentally ill.
He can find a cure the same way Hillary somehow found a cure for her "advanced Parkinson’s disease." ;-)
The real question is, which presidents WEREN'T mentally ill? You have to at least be a mass murderer-sociopath.
You can tell when a leftist's ammo box is running low when the mentally ill accusations come out. That said, there's something mentally ill about all people who seek power best I can tell. Greenbulldog, possibly Washington wasn't since grade-school history seems to indicate he was drafted into the job, but that may be historical embellishment like the cherry tree. I've never bothered to research it.
For once Krugman is speaking on a subject he knows about first-hand.
I see references to this claim all over the internet. More than any other Trump related issue. What is it about this somewhat childish but ultimately pointless claim that so gets under the skin of Trump detractors?