Elon Musk Said Antisemitic Social-Media Post Was ‘the Actual Truth’

Musk, the billionaire owner of X, formerly Twitter, responded to a user’s post Wednesday that espoused an antisemitic conspiracy theory with: “You have said the actual truth."

Musk seemed to qualify his response in a later post, agreeing with another user who said it was unfair to say Jewish communities “promote dialectical hatred towards white" people. “This does not extend to all Jewish communities," Musk replied, “but it is also not just limited to the ADL," referring to the Anti-Defamation League, a Jewish advocacy group.

The posts come amid a record-level of antisemitic incidents reported in the U.S., and as Jewish and Muslim Americans experience a rise in harassment during the Israel-Hamas war. Musk, currently considered the world’s richest person, has come under fire from Jewish advocacy organizations because of a reported rise in antisemitic posts on X since he took over the platform last year.

A representative for X declined to comment Thursday. A lawyer for Musk didn’t respond to a request for comment.

In September, Musk said he was “against antisemitism" and against “anything that promotes hate and conflict" in a conversation with Israeli Prime Minister Benjamin Netanyahu. X said earlier this year it was working to combat antisemitism on its platform.

The billionaire on Wednesday was responding to an X user’s post promoting a conspiracy theory that contends Jewish people are bringing nonwhite immigrants into the U.S. as part of an effort to reduce the white population. This conspiracy theory, which has several variations, was referenced by the gunman who killed 11 people at a Pittsburgh synagogue in 2018.

In several posts on X Wednesday, Musk said the ADL “unjustly attacks the majority of the West, despite the majority of the West supporting the Jewish people and Israel."

“This is because they cannot, by their own tenets, criticize the minority groups who are their primary threat," Musk wrote.

“At the risk of being repetitive," Musk added in an X post Wednesday, “I am deeply offended by ADL’s messaging and any other groups who push de facto anti-white racism or anti-Asian racism or racism of any kind. I’m sick of it. Stop now."

Jonathan Greenblatt, chief executive of the ADL, criticized Musk’s comments in a post on X Thursday.

“At a time when antisemitism is exploding in America and surging around the world, it is indisputably dangerous to use one’s influence to validate and promote antisemitic theories," Greenblatt said.

A representative from the ADL didn’t respond to requests for further comment.

The posts represent the latest fray between Musk and the ADL. The organization has accused Musk of allowing antisemitic and other hate speech to spread on his social-media platform. In September, Musk said the ADL was falsely accusing him of antisemitism and putting pressure on advertisers on X. He also threatened to sue the ADL for defamation in a post on X.

The ADL in October denied it pushed advertisers to boycott the platform. The ADL said it would resume advertising on X last month and sought to work with leaders at the company moving forward.

Write to Jennifer Calfas at jennifer.calfas@wsj.com