WASHINGTON - A furious President Donald Trump has plunged into open warfare with his one-time chief strategist Steve Bannon, accusing him of having "lost his mind" after being fired from his White House job.
The cause for the spite was Mr Bannon's scornful comments in a new book, "Fire and Fury: Inside the Trump White House" to the effect that Mr Trump did not really want the presidency, was campaigning for office just for the fame, and was stunned and unprepared when he actually won.
How the fallout from the book will affect Mr Bannon's role remains to be seen. But amid the blizzard of almost salacious gossip unearthed by the author, Michael Wolff - himself a controversial figure who was apparently given free run of the White House by Mr Trump - one remark by Mr Bannon stands out.
He apparently told the author he considered a meeting the president's son, Donald Trump Jr, and others had during the 2016 election campaign with a group of Russians, who were ostensibly offering information damaging to his father's rival, Hillary Clinton, "treasonous" and "unpatriotic."
Although those descriptions remain Mr Bannon's opinion, analysts say they erode the White House's narrative that there was no collusion with any Russians during the campaign - a matter being investigated by a Special Counsel, Robert Mueller.
Mr Trump has denounced the Mueller investigation as a witch hunt, but Mr Bannon's opinion of the crucial meeting could be awkward for the president.
The president fired Mr Bannon last August. The 64-year-old had been a cheerleader for Mr Trump's "America First" agenda - but apparently had a tense relationship with the president's son-in-law and top aide, Jared Kushner.
After being fired, however, Mr Bannon continued to champion the president while attacking Republicans he considered too mainstream which led analysts to conclude that he was, in effect, igniting a "civil war" within the party which now controls the White House as well as Congress.
"If I were the president I would be very uncomfortable trashing somebody with whom I worked so closely for so long, because who knows what else Mr Bannon might want to talk about," independent Senator Angus King told CNN.
Mr Bannon once described himself as a "Leninist" who wanted to "bring everything crashing down and destroy all of today's establishment." When Mr Trump won the election, he said the agenda was the "deconstruction of the administrative state."
Mr Bannon has cultivated an image as a maverick and street fighter. Ideologically he is widely seen as a white nationalist, but he has dismissed this, describing himself, instead, as an economic nationalist. He once referred to Mr Trump as his "blunt instrument."
His own clout however, took a dent last month when Roy Moore, the Republican candidate he campaigned for in a special election the senate seat in Alabama, lost.
"Trump's base loves Bannon" a political analyst who asked not to be named, told The Straits Times. "But Bannon is an agitator. He doesn't care about the party. He just wants chaos."
The Washington Post, quoting Mr Bannon's allies, has reported, however, that he considered issuing a statement denouncing the book and denying some of his quotes, but Mr Trump attacked him first.
And, in a sign, that he may still back down, Mr Bannon struck a conciliatory note on his Breitbart News Tonight radio show on Wednesday night, telling a caller "the President of the United States is a great man."
"You know I support him day in and day out, whether going through the country giving the Trump miracle speech or on the show or on the website," he said.
How Mr Trump reacts to these feelers is anybody's guess.