Reporter Jon Karl talked with the Washington Post's Karen Tumulty on Tuesday about his new book about the final days of Donald Trump's presidency, titled "Betrayal: The Final Act of the Trump Show."

In the interview, Karl talked about the role Trump loyalist Johnny McEntee played in systematically purging the Trump administration of officials whom he deemed to have insufficient fealty to the former president, which meant that those who remained in the White House at the end of his term were the hardest of the hardcore loyalists.

The result of this, said Karl, was that no one in the White House was willing to stop his potentially illegal efforts to overturn the results of the election.

"McEntee was able to get rid of officials who were not sufficiently loyal, and he was also able to frighten people into silence," Karl explained. "So when Trump took that dark, dark turn after the election, there was really nobody around him who was willing to question him, to push back on him, to rein him in, to challenge him... because they were all either fired, or scared into silence."

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Karl then marveled that McEntee could wield such power in the White House despite being so young.

"That's Johnny McEntee, 29 years old, bossing around Cabinet secretaries and junior assistants and everybody in between."

Watch the video below.

Jon Karl talked with the Washington Post's about the final days of Trump's presidency www.youtube.com