President Donald Trump remains commander in chief for only more 10 weeks, until President-elect Joe Biden takes office in January. But during that time, Trump is in a position to make destabilizing foreign policy choices that could sow chaos and restrict Bidens future policies.

While the president has been raging on Twitter about an election he sees as illegitimate, his administration is rapidly exerting control over key national security positions elevating the risk of mayhem and alarming experienced officials across Washington, D.C.

On Monday, Trump fired Defense Secretary Mike Esper, removing one of the key officials who have, to some degree, pushed back against the presidents plans. He replaced Esper with Christopher Miller , the former head of the National Counterterrorism Center, who is known for encouraging the U.S. to more aggressively confront Iran, which Trump allies want to pressure before the president leaves office.

A series of further personnel moves at the Pentagon followed: Top defense officials resigned and were replaced by Trump loyalists, including Anthony Tata, who has called former President Barack Obama a terrorist leader and has pushed a range of unhinged conspiracy theories, and GOP operatives Kash Patel and Ezra Cohen-Watnick.

It is hard to overstate just how dangerous high-level turnover at the Department of Defense is during a period of presidential transition, House Armed Services Committee chairman Adam Smith (D-Calif.) said Tuesday.

And at the National Security Agency, Trump installed Michael Ellis, who was previously involved in Republican efforts to question Russian interference in the 2016 election, as general counsel, according to The Washington Post . Ellis has been transferred to a civil servant position, making it harder for Biden to remove him, CNN reported .

The president is desperate to declassify intelligence on Moscows meddling to justify his 2016 win, regardless of how that might hurt sensitive research methods and American alliances, the Post reported on Wednesday.

Experts and Democratic operatives said the risk of vengeful or irresponsible moves by Trump is particularly high when it comes to foreign policy, an area in which the president can often act unilaterally.

The only thing that has kept Donald Trump from doing things that would have been absolutely crazy, and I would underscore absolutely, was the prospect of reelection and political pressure, said a former Obama administration official who requested anonymity to speak frankly. In a transition period, The limited guardrails that have been on this presidency would no longer be there.

We would see this president take precipitous action in ways that would be counter to our national interest but then would also set in motion crises that the Biden administration would have to account for, the former official added.

The possibilities worrying the ex-Obama staffer and others range from Trump launching a war, to using an executive order he signed last month to place political loyalists in some influential roles usually held by civil servants.

And the personnel moves in the national security arena go well beyond just the Pentagon and National Security Agency. Its clear a thorough purge is underway. On Friday, Trump ousted Bonnie Glick, a former foreign service officer serving as the deputy head of the sprawling U.S. Agency for International Development. The move kept his controversial appointee John Barsa in charge of the organization, despite the fact that his term as acting chief has expired . On Monday, Barsa told his team the transition of power to Biden has not yet begun, CNBC reported .

Trump also forced Lisa Gordon-Hagerty, the administrator of the agency that oversees Americas nuclear stockpile, out of her job on Friday. That the Secretary of Energy effectively demanded her resignation during this time of uncertainty demonstrates he doesnt know what hes doing in national security matters, Sen. Jim Inhofe (R-Okla.) , the chair of the Senate Armed Services Committee, said.

Trumps General Services Administration chief, Emily Murphy, has also refused to sign a letter granting resources to Bidens transition team, the Post reported on Sunday night, subverting a normal practice seemingly because of the presidents dishonest claims that the election is still not settled. That denies Biden not only taxpayer funding and computer systems but also full intelligence briefings , which former House Intelligence Committee Chairman Mike Rogers, a Republican, said the president-elect should already be receiving.

A longtime Trump adviser told HuffPost he believes that CIA director Gina Haspel and FBI director Christopher Wray could also be removed soon.

Bidens team cant do much to rein Trump in. They want to respect the fact that the U.S. only has one president at a time not least because of Democratic frustration with Trump acting as though he was already in charge when dealing with Russia, Israel and the United Arab Emirates before Obama left office in 2016. They also know the country will already be tense as Trump pursues lawsuits to deny Bidens victory and baselessly alleges election fraud; they dont want more squabbling that undermines Americans and foreigners faith in the U.S. commitment to an orderly and peaceful transition of power.