Stephen Miller declared it is time to ‘fight with all of our soul’ for Donald Trump after being made the US president’s new chief of staff.

Mr Trump announced on Friday that Mr Miller would replace his ‘ice queen’ Susie Wiles in the role following devastating midterm elections that saw the Republicans trounced in both the House and the Senate.

Democrats described the decision as a ‘disgrace’, with one referring to Mr Miller as a ‘malignant tumor’ that should be removed from government.

The appointment to a key role of Mr Miller, seen as the mastermind of the Trump administration’s immigration policies, signals a willingness to fight it out with a Democrat-dominated Congress.

Mr Miller immediately struck a combative tone, posting on X: ‘The mission now is more clear than ever: Fight with all of our soul to support our president and defend this magnificent republic.’

Speaking in front of Mr Trump at the president’s Mar-a-Lago base in Florida after the appointment was confirmed, Mr Miller pledged his ‘absolute loyalty and total devotion’ to his boss.

He said: ‘It was the privilege of a lifetime to join President Trump all the way back in 2015 when he came down that golden escalator and let me tell you, if it was not for President Trump, the United States of America would not exist right now. 

‘This man saved America. He saved our military from collapse, he saved our economy from destruction, he saved our border from annihilation and he saved our country from threats at home and abroad which would’ve been the end of the American dream forever.

‘We need to stand with the man who has stood with us with every fiber of his being. It is the honor of my life time to be President Trump’s chief of staff and I promise to you Mr President, my absolute loyalty, my unwavering commitment and total devotion to your success and the success of this country.’

California governor Gavin Newsom called Mr Miller a ‘vile thug’ and called the appointment an insult to those who had just rejected the MAGA movement at the polls.

Mr Newsom posted: ‘Miller cooked up the sadistic mass deportation regime that ripped apart families and trampled basic civil rights. Innocent people are dead because of him. Voters rejected his cruelty and extremism. This is sick.’

Mr Trump’s health secretary Robert F Kennedy Jr praised the appointment, describing it as ‘unleashing the Kraken’.

He posted: ‘Next to me, Stephen Miller is the strongest MAHA (Make America Healthy Again) supporter in the administration. It’s time to unleash the Kraken.’

Secretary of War Pete Hegseth, who is rumoured to be facing the axe over the disastrous war on Iran, also backed the move, writing: ‘Huge CONGRATS to @StephenM — a true patriot and America First fighter. He never backs down — and the @DeptofWar is right there with him.’

Mr Millier is notorious for calling Alex Pretti, who was shot and killed by ICE officials during a massive deportation operation in Minneapolis, a ‘domestic terrorist’ and an ‘assassin’. This year he referred to James Talarico, who won the Senate race in Texas, was the Democrats’ ‘first transgender Senate candidate’.

Democratic House leader Hakeem Jeffries wrote on X: ‘Stephen Miller is a dangerous xenophobe and reckless extremist who has American blood on his hands. His presence in government should be eradicated like a malignant tumor.’

Ms Wiles, a key member of Mr Trump’s 2024 re-election campaign, has been seen by many as ‘the adult in the room’ during the president’s second term.

However, accusations from fellow Republicans, including Calley Means, have seen her stock plummet with the president.

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