Mark Updegrove, the author of the book, talked to both Bushes on the record and they made it clear a year ago they were none too happy about the former reality television star becoming president. "And I'm not too excited about him being (our) leader". Bush Sr actually voted for Trump's Democratic rival Hillary Clinton, while the younger Bush left the space blank on the ballot.
It really was no secret that the Bushes aren't really big fans of President Donald Trump.
You can read the whole report here.
Indeed, at one point during the 2016 presidential campaign, the younger Bush confided to the author, "I'm anxious that I will be the last Republican president".
The younger Bush, meanwhile, was skeptical about then-candidate Trump's chances in a race in which his younger brother Jeb was an early favorite.
Mark Updegrove, the author of "The Last Republicans", told CNN: "It makes ideal sense". Donald Trump's election marked the end not only to the Bushes' hold on the White House, but of a rejection of the Republican principles of civility and global engagement and leadership that the Bushes have long championed.More news: Bomber's brother faces arrest in UK
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The book by Mark K. Updegrove was previewed by The New York Times and CNN on Friday.
"You can either exploit the anger, incite it", George W. Bush told Updegrove, "or you can come up with ideas to deal with it".
A White House official hit back, telling CNN: "If one presidential candidate can disassemble a political party, it speaks volumes about how strong a legacy its past two presidents really had".
Just last month, George W. Bush delivered a speech that seemed to call out so-called Trumpism - and the bigotry, conspiracy theories and "casual cruelty" associated with it. "I think his heart operation made a difference". I wasn't that fond of him.
The younger Bush resented the implication that anyone was steering him.
They "didn't make one f****ing decision", he told Updegrove.
But he insisted Cheney served him well and said the vice president's sometimes dark reputation was inevitable. "Somebody has to be the bad guy".