As Sen. John McCain (R-Ariz.) remains in his home state recovering from surgery for an intestinal infection and undergoing treatment for brain cancer, he has mostly been receiving a stream of well wishes and tributes for his long career in public service. One faction that has been a notable exception are some of President Trump's staunch defenders.

In his new memoir to be released later this month, McCain offers a harsh assessment of Trump’s leadership and says he feels less constrained to share his thoughts because he is not seeking reelection.

The longtime senator and Vietnam War veteran takes particular aim at Trump, who during his campaign dismissed the idea that McCain was a war hero, writing that he “has declined to distinguish the actions of our government from the crimes of despotic ones.”

“The appearance of toughness, or a reality show facsimile of toughness, seems to matter more than any of our values,” McCain wrote.

According to NBC News, McCain's 2008 campaign rival, former president Barack Obama, will eulogize him, and McCain doesn't even want Trump in the building.

This deepening rejection of Trump — and embrace of Obama — was not well received by many of Trump's most vocal supporters.

Corey Jones, a state director for the New Right, a political organization focused on uniting conservatives supportive of Trump's “America First” agenda, told The Fix that McCain has been preoccupied by criticizing Trump.

“I think McCain comes off as a very bitter individual,” Jones said. “Instead of leaving the past in the past, McCain has made it a mission of his to undermine the Trump agenda. Trump made some strong remarks toward Senator McCain during the election, and McCain can’t seem to move on. McCain should worry less about who he is and isn’t inviting to his funeral, and worry more about repairing his damaged legacy.”

Criticism of McCain abounded on social media, with Trump defenders calling him a Democrat and an “embarrassment to our country,” and attacking his character in other ways.

McCain's rejection of Trumpism goes beyond the president himself.

While some believe that Trump came out of nowhere to disrupt the U.S. political system, the truth is there were a handful of Republicans who paved the way for Trump. And one of them was former Alaska governor Sarah Palin — McCain's running mate, who helped give Trump more credibility and support from the base when she endorsed him.

While McCain defends Palin's performance, the lawmaker shared his regret about picking her as his No. 2, according to a New York Times report. Instead, he reportedly wishes he would have chosen former senator Joe Lieberman, a Democrat turned independent, and writes in his book that choosing Palin over Lieberman was “another mistake that I made.”

“It was very uncalled for,” Jones said. “Palin turned a dull and boring campaign into something that had the potential of being exciting. It doesn’t matter who McCain would’ve picked as VP; he was still going to lose.”

Other Trump-supporting conservatives criticized McCain's rejection of Palin, as well.

Overall, the reaction to McCain's latest comments about Trump, the president's political impact and even his former running mate are a reminder that the current GOP is no longer McCain's party.

The electorate has moved in a direction far from the “maverick” ideals that allowed McCain to consistently attract praise from both sides of the aisle and win his party's presidential nomination. Discussions about his book, his health and arrangements for commemorating his life have put that truth in the spotlight.

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