President Donald Trump on Monday announced by tweet that he had fired Defense Secretary Mark Esper, further destabilising a government already navigating his refusal to concede election defeat to Democrat Joe Biden.
"Mark Esper has been terminated. I would like to thank him for his service," Mr Trump said on Twitter.
He announced that Christopher Miller, the current head of the National Counterterrorism Center and former special forces officer, would replace Mr Esper as acting defense secretary
Mr Esper, Mr Trump's fourth Pentagon chief in four years, was fired after 16 months in the job trying to keep his head down politically as he pursued fundamental reforms to the massive Pentagon bureaucracy and sought to reshape the US defense posture worldwide to focus on the threat of China.
But Mr Trump was angered when Mr Esper resisted pressure to deploy federal troops to quash civil unrest, and also slow-walked Mr Trump's desire for a rapid full withdrawal of US troops from Afghanistan while violence continues in the country.
Mr Trump's move, expected by many insiders, was nevertheless a shock, coming just a week after losing his bid for reelection to Democrat Joe Biden and just 10 weeks before he will depart the White House.
It added also adds to a sense of lowered security in the country, as Mr Trump refuses to accept the verdict of last Tuesday's election and has pledged to reverse it in court.
Christopher Miller, director of the National Counterterrorism Center, has been nominated by Donald Trump as the new US secretary of defence. Source: CQ Roll Call POOL
Mr Miller spent 31 years in the army, deploying in Afghanistan in 2001 and Iraq in 2003 with the special forces. After retiring, he became a consultant on clandestine operations and intelligence to the government.
In 2018-2019 he was a White House advisor on counterterrorism and transnational threats, and from 2019 was deputy assistant secretary of defense for special operations.
In August he was named director of the National Counterterrorism Center.
