Elon Musk Enters Uncharted Territory With Trump Endorsement

Roughly 30 minutes after former President Donald J. Trump was shot at a rally in Pennsylvania on Saturday, Elon Musk backed his bid for the White House.

“I fully endorse President Trump and hope for his rapid recovery,” Mr. Musk wrote on X, the social media platform he owns, sharing a video of Mr. Trump raising his fist.

In more than 100 posts after the shooting, Mr. Musk further stepped up his political speech. And on Monday, after Mr. Trump announced that Senator J.D. Vance of Ohio would be his Republican running mate, Mr. Musk posted congratulations and said it was an “excellent decision by @realDonaldTrump.”

With those moves, Mr. Musk, 53, entered uncharted territory. He broke with tradition set by the leaders of other major social media firms, none of whom have endorsed a presidential candidate. By using X as a megaphone for his politics — posting to his nearly 190 million followers — Mr. Musk also erased any air of neutrality for the platform.

Now, as the presidential election gets closer, Mr. Musk’s full-throated support for the Republican candidates raises questions about how their opponents can expect to be treated on this site.

“He can fashion the platform in his image,” said Gita Johar, a professor at Columbia Business School who studies consumer behavior. “He’s got a huge following and makes no bones on where he stands on issues and politics.”