Why the New York case is the hardest one for Donald Trump: biographer
Republican presidential candidate Donald Trump during the grand opening of the Trump International Hotel in Washington, DC, October 26, 2016. (AFP Photo/Mandel Ngan)

Donald Trump's identity is wrapped up in his money, said one of his former biographers David Cay Johnston.

Speaking to MSNBC on Monday after Trump's first day of trial in his New York case, Johnston explained that no case matters more than this one because it is about the persona the self-described billionaire has built up around himself.

"Donald is his money and that's the single most important thing to understand and it's the sum and substance of who he is," said Johnston. "He was raised by a monster of a father who was involved with the two biggest mafia families in New York and up to his eyeballs. And he taught Donald that getting the money was all that mattered. And the win is all that matters."

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As a result, Johnston explained, "Anything that would take away his appearance of being very wealthy, emphasize that word, appearance, is a threat to his very existence. That's the core of the problem Donald is facing here. This is more threatening to Donald's mind than the prospect of going to prison which he can put off as oh, that's not going to happen. He sees this happening as part of the reason he's sitting there in the courtroom because he doesn't have to be there at this stage."

For decades, Trump was able to use his father to help cover for his business failures, but this time, there's no one else to blame but himself.

"The characteristic of Donald is he's never done anything wrong," said Johnston. "Everybody else is to blame and that will be shown by his lawyers. They were trying to show, 'You did this bad thing, you did that bad thing, and our client, Mr. Trump was an absolute saint here in what he did or he was only doing normal business practice.' But Donald has always inflated things. He says Trump Tower is 68 stories high. It's only 58 stories high. He told me one day I asked him how much he was worth he told me $3 billion and what did he do? He told another reporter he was worth $5 billion. He just makes this stuff up."

Meanwhile, Judge Arthur Engoron pointed out that Trump is a "persistent fraudster," and that will hurt the future of his business, the biographer explained.

See the full interview in the video below or at the link here.

Trump biographeryoutu.be