WATCH: Trump biographer lists all the reasons it’s clear Trump is ‘beholden’ to Russia

President Donald Trump is "beholden" to the Russians, his biographer explained on MSNBC's "Deadline: White House" with Nicolle Wallace on Monday.

Journalist Tim O'Brien, author of the book Trump Nation, joined MSNBC's Nicolle Wallace to analyze the commander-in-chief's pattern of using Kremlin talking points to push conspiracy theories.

"How is Donald Trump getting his information?" Wallace asked.

"Occam's razor, the simplest answer is the way we all should think about this," O'Brien suggested.

English Franciscan friar William of Ockham posited the problem-solving principle that simpler solutions are more likely to be correct than complex explanations.

"Which is, of course, that in some level he is indebted to Russia -- either financially or diplomatically," O'Brien concluded.

"Trump has been around Russian organized crime and Russian money for probably about 15 years," he explains.

"All of these things come back to him being beholden in some fashion to Russian -- and he's behaving in ways that indicated that's clearly true," he concluded.

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