Facebook said Monday that the new policy "is supported by the well-documented rise in anti-Semitism globally and the alarming level of ignorance about the Holocaust, especially among young people." Surveys have shown some younger Americans believe the Holocaust was a myth or has been exaggerated.
The Anti-Defamation League has reported that incidents of white supremacist propaganda distributed across the U.S. jumped by more than 120% between 2018 and last year. The group also said this summer it found a number of Holocaust denial groups on Facebook, some hidden and most private.
Tech companies began promising to take a firmer stand against accounts used to promote hate and violence after a 2017 rally in Charlottesville, Virginia, where a self-described white supremacist drove into a crowd of counterprotesters. Yet Facebook and other companies have been slower to respond to posts that amplify false information, but don't pose an immediate threat of violence or other physical harm.
Zuckerberg said in a blog post Monday that he believes the new policy strikes the "right balance" in drawing the lines between what is and isn't acceptable speech.
"I've struggled with the tension between standing for free expression and the harm caused by minimizing or denying the horror of the Holocaust," he wrote. "My own thinking has evolved as I've seen data showing an increase in anti-Semitic violence, as have our wider policies on hate speech."
Zuckerberg had raised the ire of the Claims Conference, based in New York, and others with comments in 2018 to the tech website Recode that posts denying the Nazi annihilation of 6 million Jews would not necessarily be removed. He said he did not think Holocaust deniers were "intentionally" getting it wrong, and that as long as posts were not calling for harm or violence, even offensive content should be protected.
After an outcry, Zuckerberg, who is Jewish himself, clarified that while he personally found "Holocaust denial deeply offensive" he believed that "the best way to fight offensive bad speech is with good speech."
The Claims Conference on Monday said it welcomed Zuckerberg's changed approach and the company's decision to take action.
"It's a very important statement and it's a building block toward ensuring that this sort of anti-Semitism is not amplified," said Greg Schneider, the group's executive vice president.
The group on Sunday posted its 75th video testimonial from a Holocaust survivor appealing directly to Zuckerberg. Fred Kurz, an American who was born in Austria in 1937, described losing both of his parents in concentration camps.
Zuckerberg never met directly with the group but Schneider said he believes the voices of survivors and their "moral authority" made a difference.
"Honestly, I'm a little surprised it took 75 days, but I'm glad it happened," he said.
Facebook said Monday it would immediately begin removing Holocaust denial posts from Facebook and Instagram, which it owns, but it could take some time to train the company's technical systems and human moderators to enforce it on a global scale.
Another group that had pushed for Facebook to take a stricter line on Holocaust denial said Monday's move was an important step.
"Facebook is showing that it recognizes Holocaust denial for what it truly is – a form of antisemitism and therefore hate speech," Ronald Lauder, president of the World Jewish Congress, said in a prepared statement.