Mr. Musk has fallen out with prominent right-wing Americans who say they are worried that their agenda may be sidelined in favor of his own — and that he is willing to silence them on X.

The X owner and tech billionaire has boosted far-right figures in Britain, Germany and Canada with a blizzard of social media posts in recent days.

While Mark Zuckerberg and Elon Musk never did face off in that cage match, "Uncle Elon" has bested Zuck in the political arena, becoming one of the most powerful unelected figures in modern US history.