'Art of the Deal' author: If Trump had Kim Jong-un's power he would be every bit as murderous
Tony Schwartz co-wrote the 1987 book 'The Art of the Deal' with Donald Trump

One of the men who knows Donald Trump as well as anyone, said on MSNBC on Saturday that Trump's admiration for North Korean strongman Kim Jong-un is a tip-off that he would deeply enjoy being a murderous despot if given a chance.

Speaking with AM Joy host Joy Reid, who called Tony Schwartz's description of Trump "scary," the ghostwriter said Trump has mental issues.

Addressing Trump's comments that he wishes Americans revered him in the way he thinks North Koreans living in their totalitarian state revere Kim,  Reid read from a Schwartz tweet stating Trump has a "severe personality disorder" that "reporters don't know how to handle."

"In Trump's case, you cannot analyze his behaviors rationally because they're not rational" he explained. "They're a function of what's going on, or what's missing internally."

With host Reid noting Trump's praise for Kim and  Russian President Vladimir Putin - with Schwartz noting the Russian leader has had journalists "murdered" -- the author said he was willing to go to an extreme to describe the president's state of mind.

"I believe he would be murdering as many enemies as Kim Jong-un does," he stated. "That his lack of conscience and his sociopathy is so extreme -- and inner sense of emptiness -- what he has is a blend of paranoia, which I said in the tweet, and grandiosity and cruelty."

"Just take the immigrants, who are being -- the kids separated from the parents," he continued. "The cruelty is a way of punishing the people who he perceives as his enemies. So, that blend of qualities make me believe that Trump has cast his lot with authoritarians and dictators -- and they behave in predictable ways."

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