US President Donald Trump (R) shakes hands with newly sworn-in White House Chief of Staff John Kelly at the White House in Washington, DC, on July 31, 2017. JIM WATSON/AFP/Getty Images

Irish American White House Chief of Staff John F. Kelly frequently lost his temper and revealed to staffers that he thought the president was “unhinged,” Watergate journalist Bob Woodward writes in his new book “Fear.”

In one meeting, Kelly said of Trump: “He’s an idiot. It’s pointless to try to convince him of anything. He’s gone off the rails. We’re in Crazytown. I don’t even know why any of us are here. This is the worst job I’ve ever had.”

When former economic advisor Gary Cohn tried to resign after Charlottesville and Trump's inflammatory speech persuaded him not to step down, Kelly disagreed.

Read more: Trump Chief of Staff John Kelly dishonors his Irish heritage with racial comments

“I would have taken that resignation letter and shoved it up his ass six different times,” Kelly told Cohn, according to Woodward.

The book also reveals that Cohn stole letters from Trump’s desk rather than have him sign them because the letters would have untold consequences. One was unilaterally pulling the US out of NAFTA.

Read more: John Kelly, Rudy Giuliani and immigration amnesia in America

Woodward reveals that Defense Secretary Jim Mattis regularly disobeyed Trump's demand for immediate hostile action and told fellow officers the crisis would be handled his way.

Trump obsessively watched cable television despite the best efforts of staff to engage him. Reince Priebus, Kelly’s predecessor, called the presidential bedroom “the devil’s workshop.”

What do you make of the new revelations? Let us know in the comments section, below.