Elon Musk vs. Peter Navarro: Their feud over Trump's tariffs explained

• Elon Musk and Trump's trade advisor Peter Navarro have been locked in a public spat over tariffs.
• Navarro called Musk a "car assembler," and the Tesla CEO called Navarro "dumber than a sack of bricks."
• The White House has brushed the feud aside, saying "boys will be boys."

President Donald Trump's tariffs haven't only roiled global markets and decades-old geopolitical alliances — they've also disrupted the relationship between two of his top advisors.

In the days since Trump announced sweeping tariffs — a 10% baseline tariff on all countries and even higher rates for specific nations — White House DOGE Office affiliate Elon Musk and top trade advisor Peter Navarro have been locked in an ugly, public feud. Navarro has advised Trump since his first term and is a staunch advocate for tariffs. Musk has fired off a number of anti-tariff comments in April — saying there should be a "free trade zone" between the US and Europe, for example.

Here's a timeline of their days-long spat, which is moving almost as quickly and dramatically as the stock market.

Musk didn't respond to Business Insider's request for comment, and representatives for the White House directed BI to Press Secretary Karoline Leavitt's statements during a press conference.

"These are obviously two individuals who have very different views on trade and tariffs," she said. "Boys will be boys and we will let their public sparring continue."

April 2

On so-called "Liberation Day," Trump announced his tariff plan. The baseline 10% tariff went into effect on April 5 at 12:01 a.m. E.T., and higher rates kick in on April 9 at the same time.

Trump's announcement initially prompted a massive market sell-off and further fueled fears of a recession among business leaders and everyday Americans alike.

April 5

Musk bashed Navarro's academic history in a post on X, writing, "A PhD in Econ from Harvard is a bad thing, not a good thing. Results in the ego/brains>>1 problem."

Navarro got his bachelor's degree from Tuft's University, before going to Harvard for a master's in public administration and a doctorate in economics.

April 6

Navarro dialed up the heat when he spoke to Fox News about Musk's comments.

"Look, Elon, when he's in his DOGE lane, he's great. But we understand what's going on here. We just have to understand. Elon sells cars," he said.

Navarro said that the Tesla and SpaceX CEO is "simply protecting his own interests as any businessperson would do." He noted, though, that things were "fine" between the two men and that "there's no rift here."

April 7

Early Monday morning, Musk posted a video on X of Milton Friedman, the economist and free-market advocate, extolling the benefits of free trade. In the video, Friedman marvels at cross-continental the production of a pencil, whose parts are sourced from countries around the globe.

In an interview with CNBC after the not-so-subtle post, Navarro took his criticism a step further.

"He's not a car manufacturer. He's a car assembler in many cases," he said of Musk. Navarro continued that Tesla sources its parts from foreign nations.

April 8

The Tesla jab didn't go unnoticed.

Musk responded to a clip from the interview and wrote on X that "Navarro is truly a moron." In case that wasn't clear enough, he followed up by saying that Tesla has "the most American-made cars. Navarro is dumber than a sack of bricks." (Tesla Model Y is at the top of Cars.com's American-Made Index.)

The world's richest man replied again in the thread and referenced Ron Vara, the made-up scholar and apparent alter-ego Navarro referenced in various books.

Not even 20 minutes later, Musk responded to another user and jokingly corrected their spelling of Navarro's name with a play on the R-word: "*Peter Retarrdo."