The Trump adviser who triggered the president's split with Elon Musk

President Donald Trump's surprise decision to change Elon Musk's preferred pick to lead NASA may have done more to fuel the historic blowup between the two men than previously known.

The president canceled his nomination of Jared Isaacman as NASA's administrator after Musk officially left the White House on Friday.

Isaacman, a billionaire, pilot and astronaut, was close with Musk and even flew to space with Musk's Dragon program on Operation Polaris Dawn in 2024.

But he had a history of donating funds to Democrats, including recent Democratic candidates who ran against GOP senators Tim Sheehy of Montana and Bernie Moreno of Ohio in 2024.

Despite his donations, Isaacman was approved by the Senate committee in April and was expected to get confirmed this week in the Senate.

But Trump's advisor Sergio Gor, in charge of managing the White House personnel office, reportedly delivered Trump a list of Isaacman's donations to Democrats according to reporting from Axios.

Gor did not appreciate Musk's involvement in personnel matters, the report noted, as they had a tense relationship.

'This was Sergio's out-the-door 'f**k you' to Musk,' one White House official said.

Trump and Musk spoke about Issacson's record prior to their press conference last Friday.

Despite their conversation, Trump pulled Issacson's nomination on Saturday.

'After a thorough review of prior associations, I am hereby withdrawing the nomination of Jared Isaacman to head NASA,' Trump wrote on his Truth Social site.

Musk responded to the news with disappointment

'It is rare to find someone so competent and good-hearted,' Musk wrote of Isaacman on X. 

The president mused Thursday that Musk's personal attacks might have been trigged by his decision.

'I know that disturbed him He wanted and rightfully recommended somebody that I guess he knew very well. I'm sure he respected him, to run NASA. But I didn't think it was appropriate. He happened to be a Democrat, like totally Democrat,' Trump said, adding that the administration had the right to nominate a Republican to the position.

As the person in charge at the White House personnel office, Gor is a powerful aide that is rarely crossed as he influences who is allowed to work in the administration.

Gor, a long-time loyal Deputy Chief of staff to Sen. Rand Paul, left in 2019 to serve as Chief of Staff to Trump Victory Finance Committee. 

He also is a close associate of Donald Trump Jr. and and officiated Rep. Matt Gaetz's wedding in August 2021. 

Gor also co-founded Trump Jr.'s publishing company and founded a pro-Trump super PAC in the 2024 election, spending nearly $72 million.

The White House backed Gor in a statement to the Daily Mail, affirming he was a valuable White House aide. 

'Sergio is a vital member of the team and he has helped President Trump put together an Administration that is second to none. As a long-time advisor, there is nobody more capable of ensuring the government is staffed with people who are aligned with the mission to make America great again and work towards implementing the President’s agenda,' White House Communications Director Steven Cheung said. 

Since Trump's comments to reporters in the Oval Office Thursday, Musk tried to de-escalate his spiraling feud with Trump.

White House aides even tried to organize a crisis call between the warring billionaires - but peace talks appear to be off as of Friday morning.

The bromance between the world's richest and most powerful men was in tatters on Thursday with Musk calling for Trump to be impeached after linking him to Jeffrey Epstein and the president urged to deport the Space X boss.

The clash, which began over Musk's opposition to Trump's 'big, beautiful bill', quickly evolved into personal insults and prompted the president to suggest that Musk's multibillion-dollar government contracts should be ripped away.

The world's richest man suffered one of his worst ever days on Wall Street, losing around $27 billion from his net worth as frantic traders dumped Tesla stock.

Billionaire hedge fund manager Bill Ackman stepped into the fray, posting a plea on X for the two men to reconcile 'for the benefit of our great country,' warning that 'we are much stronger together than apart.'

Musk, who became one of Trump's closest allies during the election campaign and then as head of his DOGE cost cutting taskforce, responded with a brief but telling reply: 'You're not wrong.'