Despite his loud and frequent protestations, Elon Musk may be the worst ambassador for free speech in America. To understand why, it’s necessary to look at X, the website formerly known as Twitter, which he owns and rules over like the generalissimo of a banana republic. The past several days are of particular relevance.

Since the end of last month, the site has hosted a tsunami of vile antisemitic speech. While it’s difficult to peg the cause of any given trend on X, it appears that this latest wave of bigotry might have been sparked by an Aug. 29 meeting between the Anti-Defamation League chief executive, Jonathan Greenblatt, and the new X chief executive, Linda Yaccarino. As Greenblatt posted, the purpose of the meeting was to “address hate” on the platform.

What happened next was extraordinary. Almost immediately, a number of notorious antisemitic accounts posted under the hashtag #BanTheADL. Musk boosted the campaign by liking a post by a far-right activist that called for banning the A.D.L. and then started his own campaign against the organization. In a series of posts on X, he blamed it for most of X’s loss in advertising revenue, called the A.D.L. the biggest generator of antisemitism on X, proposed a poll on booting the A.D.L. from the platform and then threatened to sue the A.D.L. for defamation.

And make no mistake: As Claire Berlinski detailed in an excellent Substack post, the X discourse on the A.D.L. was hardly a nuanced critique of its priorities. Rather, it was an excuse for an outpouring of the worst rhetoric imaginable. And what was Musk’s response? He declared himself “against anti-Semitism of any kind” — though his claims of the A.D.L.’s immense power tapped into classic antisemitic tropes — but “pro free speech.”

Musk’s invocation of free speech is nothing new for him. He has called himself a “free speech absolutist,” and when he agreed to buy Twitter in 2022, he loftily declared that “free speech is the bedrock of a functioning democracy, and Twitter is the digital town square where matters vital to the future of humanity are debated.” After the platform’s previous moderation troubles — which the former Twitter chief executive Jack Dorsey openly acknowledged — there was at least some reason to hope that Musk’s purchase would result in a platform moderated in a manner broadly in accordance with First Amendment principles.

But that’s not what happened. Not at all. Instead of creating a platform for free speech, Musk created a platform for Musk’s speech — or, more precisely, Musk’s power. First, he has demonstrated that he’s perfectly willing to take action against people or entities that challenge him or challenge X. As my friends at the Foundation for Individual Rights and Expression (where I used to serve as president) have detailed, he has used his authority to suspend accounts, to throttle (or limit the traffic of) competitors and reportedly to boost his own voice.

Second, rather than create a free marketplace of ideas, Musk uses X as a marketplace where you can pay to privilege your thoughts. Under the pay-to-play system, the people who fork over a monthly fee to join X’s premium service have their reach substantially extended, including by being granted “prioritized rankings in conversations and search.” And because Musk has centered himself in the platform’s public image, a disproportionate number of these premium accounts seem to share Musk’s trollish right-wing persona and create the unmistakable sense that X is becoming dominated by far-right voices that often revel in cruelty, bigotry and misinformation.

Finally, we can’t neglect the power of Musk’s own voice to distort the debate. As Berlinski details in her newsletter, when he “calls attention” to other accounts by liking, responding or retweeting, “he makes them famous, immediately. It directs a human tidal wave of attention — some 140 million Elon Musk fans — to their accounts.”

Taken together, all of these factors mean that Twitter isn’t so much a free speech paradise as the generalissimo’s playpen, and the generalissimo’s values shape everything about the place.

An offline analogy can be helpful. One of the most significant Supreme Court cases demonstrating the reach of American free speech law is National Socialist Party of America v. Village of Skokie. The Supreme Court upheld the First Amendment rights of Nazis who sought to march through the heavily Jewish village of Skokie, Ill. The case marked the extent to which American free speech rights extend even to the most abhorrent of ideas. So yes, it’s true that a social media platform that models its policies on the First Amendment will still permit some repugnant speech.

But is that what’s happening on X? No. A closer parallel would be if the mayor of Skokie didn’t just let the Nazis march but also leased them powerful loudspeakers for a nominal fee so that Jewish citizens found it hard to ignore the Nazis’ speech, banned the speech of local citizens who angrily objected to the mayor’s rules and then occasionally grabbed a white supremacist from the crowd for a supportive interview on the mayor’s radio show. When the Jewish citizens complained, the mayor threatened their most vocal civic organization with a ruinous lawsuit. And after critics rightfully attacked this bias, the mayor claimed that he really, truly hates the Nazis; it was just that he loved free speech so very much.

No one would take such a claim at face value. It is true that a platform dedicated to free speech will tolerate even the expression of abhorrent ideas. (Indeed, as Greenblatt argued in an interview with Yair Rosenberg at The Atlantic, “We believe very strongly that hate speech is the price of free speech.”) But it is not true that free speech requires agreement or amplification. It is not true that censoring dissent or threatening dissenters is consistent with free speech.

X is Musk’s company, and he can set whatever speech rules he wishes. But do not be fooled. When Musk defends his decisions by shouting “free speech,” I’m reminded of the immortal words of Inigo Montoya in the movie “The Princess Bride”: “You keep using that word. I do not think it means what you think it means.” Musk isn’t promoting liberty; he’s using his power to privilege many of the worst voices in American life.