"I don't like him". "And I'm not too excited about him being a leader".
In light of Trump's anti-trade, anti-immigration agenda that runs counter to decades of GOP dogma, George W. Bush feared he would be seen as the "last Republican president", a quote that gave the book its title.
The younger Bush, however, was more "circumspect", according to the Times, and lamented over how much Trump bashed his younger brother - former Florida Gov. Jeb Bush - during the 2016 Republican primaries. "George Bush grew up thinking about the greater good".
Last month he said of Trump's government, "Bigotry seems emboldened".
George W. Bush didn't expect Trump to win the general election, Updegrove told CNN in an interview about the book.
Trump stood for rudeness, worldwide isolationism and weak leadership in the eyes of the Bushes, according to Updegrove - reservations echoed by many establishment Republicans.
"The American people voted to elect an outsider who is capable of implementing real, positive, and needed change - instead of a lifelong politician beholden to special interests".
Trump had recently had nice things to say about another former president, Jimmy Carter, whom he once called worst president in USA history.
In a statement, Trump's press secretary Sarah Huckabee Sanders did not repeat the White House's direct attacks on the Bush legacies from earlier in the day.