In December 2018, then-President Donald Trump announced on Twitter that he would nominate Gen. Mark Milley as the next chairman of the Joint Chiefs. Milley was not the consensus pick, and then-Defense Secretary James Mattis objected to his selection. But Trump wanted the square jawed, barrel-chested general whom he saw as straight from central casting as his top military officer.

Nearly three years later, Milley has transformed from Trump's hand-picked general -- who accompanied the President to his infamous photo-op at St. John's Church during the George Floyd protests -- to one of Trump's harshest critics in the slew of scathing books released this summer on the final months of the Trump presidency.

According to the upcoming book from Washington Post reporters Carol Leonnig and Philip Rucker, "I Alone Can Fix It," Milley was deeply concerned Trump and his allies might attempt a coup after the November 2020 election, and he compared Trump's lies about election fraud to the rhetoric used by Adolf Hitler as he rose to power in Germany.

"This is a Reichstag moment," Milley told his aides, according to the book. "The gospel of the Führer."

The startling comments in the new book were only the latest instance where Milley, who remains the chairman of the Joint Chiefs in the Biden administration, found himself in the middle of major political fights in both the Trump era and during the fallout from the January 6 insurrection.

It's an odd role for the nation's top military official to play, but one that Milley has been thrown into thanks in large part to Trump. While Milley has sought to distance himself from politics, it was often impossible to do so while working for the former President, even after he left office.

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