Trump flew into a rage after someone mentioned Ukraine – according to his former deputy national security adviser
U.S. President Donald Trump speaks during an interview with Reuters at the White House in Washington, U.S., January 17, 2018. REUTERS/Kevin Lamarque

Donald Trump's former deputy national security adviser offered a scathing assessment of his leadership abilities.

Charles Kupperman told the New York Times Magazine that the former president, who was impeached over his alleged 2019 extortion scheme against Ukraine, flew into a rage on May 23 of that year at the mention of the country's name.

“He just let loose," Kupperman recalled. "‘They’re [expletive] corrupt. They [expletive] tried to screw me.’”

Kupperman knew there was no chance that Trump understood the value of a good relationship between the U.S. and Ukraine after seeing the way he treated other allies, including France, Britain and South Korea, and he said the former president basically was not capable of making foreign policy because he didn't even understand the concept on the most basic level.

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“He felt like our allies were screwing us, and he had no sense as to why these alliances benefited us or why you need a global footprint for military and strategic capabilities,” Kupperman said. “If one were to ask him to define ‘balance of power,’ he wouldn’t know what that concept was. He’d have no idea about the history of Ukraine and why it’s in the front pages today. He wouldn’t know that Stalin starved that country. Those are the contextual points one has to take into account in the making of foreign policy."

"But he wasn’t capable of it, because he had no understanding of history: how these countries and their leadership evolved, what makes these countries tick," Kupperman added.

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