Mr. Musk lashed out at Peter Navarro, Mr. Trump's top trade adviser, as he defended the president's sweeping tariffs. "The market is going to bottom out," Mr. Navarro said on Saturday. "It's going to come very soon, and from there we're going to have a bull market boom and the Dow is going to reach 50,000 in the Trump administration." In response to a post on the social media platform touting Mr. Navarro's credentials, Mr. Musk wrote on X: "Having a PhD in economics from Harvard is not a good thing, it's a bad thing."