‘Moron’: Elon Musk slaps US President Donald Trump’s tariff czar Peter Navarro as Tesla stock hits skids

As Tesla shares plummeted for a fourth straight day, chief executive Elon Musk let loose on President Donald Trump’s top trade adviser, Peter Navarro.

Musk, the world’s richest person, started going after Navarro over the weekend, posting on X that a “PhD in econ from Harvard is a bad thing, not a good thing”, a reference to Navarro’s degree. Whatever subtlety remained at the beginning of the week has since vanished.

On Tuesday, Musk wrote, “Navarro is truly a moron” in response to the trade adviser’s remark that Tesla is more of a “car assembler” than a car manufacturer, adding that Navarro’s comments are “demonstrably false”. Musk called Navarro “dumber than a sack of bricks”, before later sarcastically apologising to bricks. Musk also called Navarro “dangerously dumb”.

Musk’s attacks on Navarro represent the most public spat between members of Trump’s inner circle since the president took office in January, and show that the steep tariffs Trump announced Wednesday on more than 180 countries and territories don’t have universal approval in the administration.

When asked about the feud in a briefing Tuesday, White House press secretary Karoline Leavitt said, “Look, these are obviously two individuals who have very different views on trade and on tariffs.”

“Boys will be boys, and we will let their public sparring continue,” she said.

Musk’s younger brother, Kimbal — a restaurant owner, entrepreneur and Tesla board member — has joined in on the action. Kimbal Musk criticised the tariffs Monday, calling them a “permanent tax on the American consumer”. He followed that up Tuesday by posting on X that the China-US standoff is “not a game that should be played by C-minus students like Peter Navarro”.

For the Tesla CEO, the name-calling appears to be tied to business conditions.

Tesla’s stock is down 22 per cent in the past four trading sessions and 45 per cent for the year. Tesla has lost more than $US585 billion ($985b) in value since the calendar turned, equalling tens of billions of dollars in paper losses for Musk, who is also CEO of SpaceX and owner of xAI and social network X.

Even before Trump detailed his plan for widespread tariffs, he’d already placed a 25 per cent tariff on vehicles not assembled in the US Many analysts said Tesla could withstand those tariffs better than competitors because its vehicles sold in the US are assembled domestically.

But the company’s production costs are poised to increase because of the tariffs on materials and parts from foreign suppliers. Canada and Mexico are among the leading sources of US steel imports, and Canada is the nation’s largest supplier of aluminium, while China and Mexico are home to major suppliers of printed circuit boards to the automotive industry.

At an event Saturday hosted by right-wing Italian Deputy Prime Minister Matteo Salvini, Musk said: “Both Europe and the United States should move, ideally, in my view, to a zero-tariff situation, effectively creating a free trade zone between Europe and North America.”

Musk, whose view on trade relations with Europe stands in stark contrast to the policies implemented by Trump, has a vested interest in the region. Tesla has a large car factory outside Berlin, and the European Commission has previously turned to SpaceX for launches.

Even before the tariffs, Tesla’s business was faltering. On Wednesday, the company reported a 13 per cent year-over-year decline in first-quarter deliveries, missing analysts’ estimates. That report landed two days after Tesla’s stock price wrapped up its worst quarter since 2022.

Musk, who spent roughly $US290 million to help return Trump to the White House, is now leading Trump’s so-called Department of Government Efficiency, or DOGE, which has slashed costs, eliminated regulations and cut tens of thousands of federal jobs.

In the first quarter, Tesla was hit with waves of protests, boycotts and some criminal activity that targeted vehicles and facilities in response to Musk’s political rhetoric and his work in the White House.

CNBC