I read one chapter twice because it concisely demonstrates Trump's abhorrent thinking, revealing the man has no moral compass. He feels sorry for Nixon because he sees him as a victim.
Trump doesn't even bother thinking about Nixon's many felonies and his total disregard for the law. The only thing that matters is Nixon was "betrayed" by people who testified against him when he believed they would be totally loyal, no matter what.
So in Trump's mind, the real villains of Watergate were not Nixon and those who remained loyal. The real bad guys were the one who revealed Nixon's many crimes.
Trump is engaging in a sort of transference here. The real problem with the President's growing scandals are not all the criminal acts he and his associates may have committed; instead, the villains are the ones working to expose Trump and bring him and his family to justice.
Here is an excerpt from Wolff's book where he talks about Trump musing aloud about his "enemies" and those of Nixon:
[White House counsel Don] McGahn tried to explain that in fact [former FBI director James] Comey himself was not running the Russia investigation, that without Comey the investigation would proceed anyway. McGahn, the lawyer whose job was necessarily to issue cautions, was a frequent target of Trump rages. Typically these would begin as a kind of exaggeration or acting and then devolve into the real thing: uncontrollable, vein-popping, ugly-face, tantrum stuff. It got primal. Now the President’s denunciations focused in a vicious fury on McGahn and his cautions about Comey.
“Comey was a rat,” repeated Trump. There were rats everywhere and you had to get rid of them. John Dean, John Dean, he repeated. “Do you know what John Dean did to Nixon?”
Trump, who saw history through personalities -- people he might have liked or disliked -- was a John Dean freak. He went bananas when a now gray and much aged Dean appeared on talk shows to compare the Trump-Russia investigation to Watergate. That would bring the President to instant attention and launch an inevitable talk-back monologue to the screen about loyalty and what people would do for media attention. It might also be accompanied by several revisionist theories Trump had about Watergate and how Nixon had been framed. And always there were rats. A rat was someone who would take you down for his own advantage. If you had a rat, you needed to kill it. And there were rats all around.
Later, it was [former White House advisor Steven] Bannon who had to take the President aside and tell him that John Dean had been the White House counsel in the Nixon administration, so maybe it would be a good idea to lighten up on McGahn.