Billionaire presidential adviser Elon Musk attacked White House trade counselor Peter Navarro as “dumber than a sack of bricks” as a fight over President Donald Trump’s tariff regime spilled onto social media on Tuesday.

In a flurry of posts on his social media platform X, Musk called Navarro “truly a moron” and mocked the trade adviser for in the past citing the work of “Ron Vara” — a fictional expert whose name is an anagram of his own.