On his first day as Chief of Staff, former Marine Corps general John Kelly got President Donald Trump to fire the abrasive communications director Anthony Scaramucci - a sign, analysts say, that he was serious about bringing order to a seemingly chaotic White House.
But there remains scepticism whether Mr Kelly can succeed with a White House riven by internecine fighting and media leaks, and a mercurial President.
Mr Scaramucci, the fast-talking former financier who shocked Washington when he let loose an obscene tirade about his colleagues to a reporter, lasted 10 days.
"A great day at the White House!" the President tweeted, hours after press secretary Sarah Sanders announced that Mr Scaramucci "does not have a role at this time".
Pressed on the issue, she said: "The President certainly felt that Anthony's comments were inappropriate."
Mr Trump announced Mr Kelly's appointment last Friday, after the abrupt - though not unexpected - departure of chief of staff Reince Priebus, whom Mr Scaramucci - known as "The Mooch" - had excoriated. Mr Scaramucci was fired after discussions at the weekend.
In an unusual arrangement, Mr Scaramucci had been appointed to report directly to the President, bypassing Mr Priebus. With Mr Kelly in charge, the lines of command have reverted to normal, with the former general - brought from his job as head of Homeland Security - being given full authority.
"Kelly is already changing the culture here," an unnamed White House aide told the Politico website.
But analysts say firing Mr Scaramucci was the easy part, and it remains uncertain whether Mr Kelly can bring a sense of unity and coherence to a White House run by a President whose management style is to encourage "healthy competition" among his own staff.
"Some observers have welcomed Kelly's hiring as evidence that perhaps the President is learning, that maybe now we will have a disciplined White House that will focus on the business of public policy," Professor Eliot Cohen, director of the Strategic Studies Programme at the Johns Hopkins University School of Advanced International Studies, wrote in The Atlantic just before Mr Scaramucci got the boot.
But he added: "Trump will remain Trump, and the various denizens of the White House are unlikely to treat Kelly with much more deference than they treat one another. He will discover that he is no longer a general, or even a Cabinet secretary, but a political functionary - neither more nor less."
An analyst who asked not to be named told The Straits Times: "I seriously wish he could impose some order. What scares me is that for six, seven months, everything has been self-inflicted. There has not been one international crisis."
He was not optimistic. "Kelly sent a clear message with (Mr Scaramucci) but I do not think that anyone is capable of imposing order on that lot," he said. "There is so much infighting, back-stabbing and overall incompetence. Kelly will become complicit. For Trump, loyalty is a one-way street, and it is highly conditional."
Professor of American Studies Glenn Altschuler at Cornell University said: "Every time a new person is appointed to a position in any administration, there is speculation that that person will bring order where there has been chaos...
"What Mr Kelly will find is that this White House does not respond as the military does to chain of command and orders."
In an e-mail to The Straits Times, Prof Cohen wrote: "It (Mr Scaramucci's firing) clearly marks Kelly's tenure as a no-nonsense chief of staff. But at the end of the day, I do not believe that he will be able to contain the President, who remains the boss."