'There's no moral core': Trump biographer explains why the president can't comfort grieving families

President Donald Trump is incapable of caring about others, according to his biographer David Cay Johnston.

During an interview with SiriusXMProgress host Dean Obeidallah, Johnston was asked why the president could fail at something so easy as comforting people in a time of tragedy.

"There's no moral core to Donald," Johnston explained. "He's deeply mentally ill, and he doesn't have any philosophy except himself."

Obeidallah went more in-depth, asking if there was anything the president wasn't willing to do to keep himself in office.

"The only thing that would inhibit him would be a fear that he, himself, would pay some penalty for it like being arrested," he explained. "The people who think that if he loses both the popular and electoral college vote that he won't leave the White House -- the Secret Service will strong-arm walk him out of the building Jan. 20, 2021 if that's the case."

Listen to the full interview below: