WASHINGTON — John F. Kelly, President Trump’s new chief of staff, firmly asserted his authority on his first day in the White House on Monday, telling aides he will impose military discipline on a free-for-all West Wing and underscoring his intent by firing Anthony Scaramucci, the bombastic communications director, 10 days after he was hired.
Mr. Scaramucci was forced out of his post, with the blessing of the president and his family, just days after unloading a crude verbal tirade against other members of the president’s staff, including Reince Priebus, Mr. Kelly’s beleaguered predecessor, and Stephen K. Bannon, the chief White House strategist.
Mr. Trump recruited Mr. Scaramucci as a tough-talking alter ego who would ferociously fight for him the way others had not. But “the Mooch,” as he likes to be known, quickly went too far, even though working a president who delights in pushing boundaries of political and social decorum. As Mr. Kelly, a former four-star Marine general, began his first day on the job, Sarah Huckabee Sanders, the White House press secretary, announced that Mr. Scaramucci was out.
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“The president certainly felt that Anthony’s comments were inappropriate for a person in that position,” Ms. Sanders said. “He didn’t want to burden General Kelly, also, with that line of succession.”
In a post to Twitter just hours before the announcement, Mr. Trump insisted that there had been “No WH chaos!” Yet even as he sought to reassure supporters that all was well, several administration aides fretted that the impetuous president and the disciplined Marine were already on a collision course that could ultimately doom the unlikely partnership.
Mr. Kelly, the first former general to occupy the gatekeeper’s post since Alexander Haig played that role for President Richard M. Nixon during Watergate, is charged with quelling the chaos that has defined, distracted and often derailed Mr. Trump’s White House. But the president gave Mr. Priebus many of the same assurances of control, and then proceeded to undercut and ignore him — to the point where Mr. Priebus often positioned himself at the door of the Oval Office to find out whom the president was talking to.
Mr. Scaramucci epitomized the chaos of the West Wing. As a wealthy New York financier, he burst onto the political scene with a memorable performance in the White House briefing room, where he portrayed himself as a major, new player who had been assured he would report directly to the president, without the interference of intermediaries like Mr. Priebus or Sean Spicer, the president’s first press secretary.
It was soon clear that Mr. Scaramucci wouldn’t be a fixture of the administration, but a transitory figure who created an opportunity for Mr. Trump, with his daughter Ivanka and son-in-law Jared Kushner, to undertake the far-reaching shake-up intended to purge the White House staff of leakers and aides viewed as not sufficiently loyal to his cause.
Mr. Spicer quit the day Mr. Scaramucci was hired; Mr. Priebus left shortly after the rant in which Mr. Scaramucci accused him of undermining the president through leaks of information to reporters.
Mr. Kelly, who was Mr. Trump’s first secretary of homeland security, arrives at a critical juncture, when the president is confronted with North Korea’s growing nuclear ambitions, Russia’s aggressive diplomatic moves and continuing fighting in Iraq and Syria. The new chief of staff will also be charged with reviving a stalled legislative agenda. Mr. Trump’s campaign promise to repeal and replace the Affordable Care Act ended in failure last week, and there has been little progress on other major goals like tax reform or rebuilding the nation’s infrastructure.
And despite his desire for discipline, it took only hours on Monday for Mr. Kelly to face his first White House leak, and it was about him. CNN reported that Mr. Kelly had been so upset about the president’s firing of James B. Comey, the former F.B.I. director, in May that he called Mr. Comey to say he was considering resigning, an account that was confirmed by a former law enforcement official who was told of the conversation.
Mr. Kelly resisted the president’s entreaties to take over for Mr. Priebus during the past several weeks. After his appointment was announced on Friday, he met with Mr. Trump and demanded assurances that he would wield the usual, sweeping authority over personnel, the flow of information and access to the Oval Office that chiefs of staff have traditionally been given.
In early morning staff meetings at the White House on Monday, Mr. Kelly made it clear that the president had agreed to let him impose more discipline over what had been an unruly and inefficient decision-making and communications process under Mr. Priebus, who had none of Mr. Kelly’s experience in government or the military.
Mr. Kelly also made it clear that everyone in the staff — including Mr. Bannon, Ms. Trump and Mr. Kushner — will clear policy proposals, personnel recommendations and advice from outsiders through him.
“General Kelly has the full authority to operate within the White House, and all staff will report to him,” Ms. Sanders told reporters later. But she added that Mr. Trump would decide how that would work.
Mr. Scaramucci’s fall and Mr. Kelly’s rise highlighted the diminished but still important role in shaping the West Wing played by Ms. Trump and Mr. Kushner, both of whom serve in the White House as senior advisers to the president.
Ms. Trump and Mr. Kushner had hoped to persuade Mr. Trump to appoint Dina Powell, the deputy national security adviser, as chief of staff, but later — when it became apparent that Mr. Trump had settled on hiring Mr. Kelly — supported the choice of the general, according to people involved in the White House’s internal discussions.
While Mr. Kelly’s concerns were the decisive factor in Mr. Scaramucci’s departure, they said, it was clear that Mr. Trump had quickly soured on the wisecracking, Long Island-bred former hedge fund manager, and so had his family.
Ms. Trump and Mr. Kushner had initially pushed the president to hire Mr. Scaramucci, seeing him as a way to force out Mr. Priebus, former Republican National Committee chairman, and his allies in the West Wing, like Mr. Spicer.
Mr. Spicer resigned just hours after Mr. Scaramucci’s hiring was made public. And shortly after Mr. Scaramucci called Mr. Priebus a “paranoid schizophrenic, a paranoiac” — adding a more vulgar term to the beginning of the phrase — Mr. Priebus, too, offered his resignation.
Mr. Trump was initially pleased by Mr. Scaramucci’s harsh remarks, directed at Mr. Priebus as well as Mr. Bannon. But that view seemed to change as people around Mr. Trump told him that Mr. Scaramucci’s over-the-top performances were not well received.
In addition, Mr. Scaramucci seemed to be, at least for the moment, overshadowing him — a fact that Breitbart News, which Mr. Bannon used to run, pointed out in a headline describing Mr. Trump as second fiddle to his communications director.
Over the weekend, after speaking with his family and Mr. Kelly — who refused to even consider retaining Mr. Scaramucci — the president began to see the brash actions of his newly high-profile subordinate as a political liability, according to three people familiar with his thinking.
For the time being, the White House may leave the communications director post open, said a person close to the internal discussions about the job, though Mr. Kelly has the latitude from Mr. Trump to fill the post with someone from the Department of Homeland Security.
Two perennial candidates to fill the post are Kellyanne Conway, a White House senior adviser and the president’s former campaign manager, and Jason Miller, who held the communications post during the campaign. Mr. Trump has long wanted to bring Mr. Miller, who serves as an informal adviser, into the administration.
Mr. Kelly’s bond with the president is based on Mr. Trump’s affinity for generals, whom he views as can-do leaders, and a belief that Mr. Kelly is a “star” of the administration, delivering on the promise to secure the border and toughen immigration enforcement.
But the choice was also part of a bet that Mr. Kelly can tame a White House that has at times seemed out of control, even to those inside it. On Monday, after a day that included a cabinet meeting and a ceremony to present the Medal of Honor, Mr. Trump seemed eager for the normalcy that has so far eluded him.
At 6:19 p.m., he tweeted: “A great day at the White House!”