Elon Musk slammed President Trump’s top trade adviser as “dumber than a sack of bricks” on Tuesday as tensions between the two exploded over wide-ranging tariffs that have upended the global economy.
Mr. Musk directed the criticism at the trade adviser, Peter Navarro, who on Monday said Mr. Musk was not a “car manufacturer” but a “car assembler” because Tesla, his electric vehicle company, relied on parts from around the world.
Mr. Musk fired back, defending his company and calling Mr. Navarro a “moron.” Mr. Navarro, he said, should consult “the fake expert he invented, Ron Vara” — the imaginary source Mr. Navarro invented for many of his economic books. Mr. Musk is estimated to have lost roughly $31 billion since Mr. Trump’s tariff announcement, according to the Bloomberg Billionaires Index.
The feud between two of Mr. Trump’s top advisers has played out on social media for days as the administration’s new tariffs have caused huge losses across global financial markets. Among staff at the White House, Mr. Musk’s latest attacks on Mr. Navarro generated more laughs than concern, according to multiple officials who requested anonymity to discuss private conversations.
So far, Mr. Trump has not weighed in on the spat between his top aides, both of whom he holds in high regard. Mr. Navarro was a senior official on trade issues during Mr. Trump’s first term and remained loyal to the president afterward, even spending four months in jail after being convicted of contempt of Congress for refusing to testify in its investigation into the Jan. 6, 2021, attack on the Capitol.
Mr. Musk’s criticism is notable because of how rarely he breaks with Mr. Trump since enmeshing himself in the president’s inner circle. Mr. Musk often travels with him to Florida on weekends, though he was not part of the president’s entourage last weekend.
Mr. Musk has spent the past several days criticizing Mr. Navarro and publicly airing his disagreement over Mr. Trump’s tariffs. He chastised Mr. Navarro for having a Ph.D. in economics from Harvard, writing that was “a bad thing, not a good thing” and then posted that Mr. Navarro “ain’t built” anything, using an expletive. (He later deleted the second post.)
Mr. Musk, the world’s wealthiest man and a top adviser to the president, has called for “zero tariffs” between the United States and Europe, rejecting Mr. Trump’s approach.
On Monday, Mr. Navarro, a strident trade hawk, said on CNBC that he had not yet spoken with Mr. Musk but downplayed any tension.
“Everything is good with Elon,” Mr. Navarro said. On Sunday, he had downplayed the tension by suggesting Mr. Musk was simply protecting his interests like any business executive would do.
Mr. Musk often uses his X account to barrage his critics, insulting them and inciting his nearly 219 million followers to join in. He has rarely been held accountable for his inflammatory posts. Since acquiring Twitter and renaming it X, Mr. Musk has often targeted judges who try to hold him or his companies to account. And in recent months, Mr. Musk lashed out at judges who have slowed or halted his federal cost-cutting efforts at the Department of Government Efficiency.
Kate Conger and Maggie Haberman contributed reporting.
