US President Donald Trump fired Secretary of State Rex Tillerson on Tuesday, drawing a line under a tumultuous relationship that saw the men frequently at odds over America's key alliances and role in the world.
Mr Trump took to Twitter to unceremoniously sack Mr Tillerson and is expected to replace him with CIA Director Mike Pompeo.
Mr Pompeo's successor is likely to be Gina Haspel, who will be the first female director of the intelligence agency if confirmed.
Undersecretary of State Steve Goldstein and other State Department officials said that Mr Tillerson hadn't learned he was dismissed until he saw Mr Trump's early-morning tweet. Mr Goldstein was also dismissed soon after.
Mr Tillerson's departure, the latest in a long line of White House sackings, introduced a number of firsts – the first firing of a US secretary of state less than 18 months on the job; the first to happen on Twitter; and the first to be revealed to the public before the secretary himself.
Mr Tillerson had just landed in Washington from a week-long trip in Africa when he was reportedly notified of the dismissal by his chief of staff, Margaret Peterlin, who showed him Mr Trump’s tweet.
"We disagreed on things," Mr Trump said – a diplomatic take on a fractious relationship, including reports that Mr Tillerson had privately called the president a "moron".
The dismissal of Mr Tillerson is yet another illustration of the gulf that has long separated him and the US president.
The two clashed on a number of issues, including the Iran nuclear deal, the Paris agreement, North Korea, the Qatar dispute, the Jerusalem embassy move, NAFTA negotiations and State Department appointments.
"The secretary had every intention of remaining because of the tangible progress made on critical national security issues," a statement issued by former aide Mr Goldstein had said. He confirmed that Mr Tillerson had not been informed of the reason for his firing, but that the former secretary of state was "grateful for the opportunity to serve".
Experts and former US officials in Washington who spoke to The National did not express shock at the sudden reshuffle.
“It is a real achievement to be too incompetent for the Trump administration, but Rex Tillerson stands out even among the cast of clowns in Trump's cabinet,” said Ken Gude of the Centre for American Progress.
Mr Tillerson, he said, “will be remembered for his closeness to Vladimir Putin and a disastrous attempt at reorganisation that only produced an exodus of senior diplomats that leaves the US dangerously ill-equipped to meet the challenges of today's global security environment”.
Henri Barkey, a former State Department official and senior fellow at the Council on Foreign Relations, said that Mr Tillerson’s departure might be good for the State Department. “He ran the department horribly, did not understand what a public institution does or manage its people.”
Under Mr Tillerson, a number of senior positions and key embassy appointments remained empty and some prominent diplomats left the department.
"He thought leaving offices empty was a sign of good governance and reduction of excess," Mr Barkey told The National. Mr Pompeo "is likely going to be more attuned to the department's needs".
Indeed Mr Pompeo’s views are more aligned with those of Mr Trump. “We're always on the same wavelength. The relationship has been very good, and that's what I need as secretary of state," Mr Trump said.
The incoming secretary of state is expected to bring a more hawkish line on terrorism and Iran.
However, Mr Barkey cautioned against exaggerating the extreme to which Mr Pompeo would go to undermine the European position on the Iran nuclear deal.
“I suspect that he will announce a tougher Iran policy without touching the Joint Comprehensive Plan of Action while trying to push back Iranian efforts at destabilising the region.”
Mr Pompeo requested a visa to monitor the Iranian elections in 2016, but the visa was denied. And last year he dispatched a letter to Iranian Major General Qassem Soleimani warning of Iran’s destabilising behaviour in Syria and Iraq.
Mr Pompeo is also more combative than his predecessor when it comes to Russia's interference and US relations with Turkey and its president, Recep Tayyip Erdogan. He told The BBC in January that Moscow will try to meddle in the US midterm elections in November.
Mr Pompeo "has said some very harsh things about Turkey and Erdogan", Aaron Stein of The Atlantic Council told The National.
In 2016, Mr Pompeo called Turkey a "totalitarian Islamist dictatorship" in a tweet that has since been deleted.
Still, Mr Stein said, Mr Pompeo will be “inheriting an effort to make things right with Ankara. The challenge he will face is exactly the challenge that Rex Tillerson is leaving behind: trying to manage the Turkey-PKK [Kurdistan’s workers party] conflict in northern Syria.”
Mr Tillerson had been an unlikely pick for top diplomat, with no formal experience but a lifetime's worth of personal relationships with heads of state and powerful global figures, including Mr Putin. He was slated to retire from Exxon in March 2017 at age 65 under the company's mandatory retirement policy when he joined the government.