Facebook’s moderators – the employees trained to delete offensive material from the site – are explicitly trained to delete posts, photos, comments, groups, pages and profiles that represent or support white supremacists, according to leaked internal materials.

But according to the documents and Facebook officials, the same does not apply to white nationalists – a group that includes people like Jason Kessler, who organised the deadly white supremacist rally in Charlottesville, and anti-immigrant groups like the VDare Foundation.

According to Facebook, moderators should delete phrases like “I’m racist and proud,” or “I’m proud to be a Nazi,” while leaving statements like “I’m a proud white nationalist,” and “White separatism is the perfect solution to America’s problems".

“Facebook are making some very arbitrary distinctions here, between groups who they would argue openly advocate hatred towards others,” said Clive Webb, a white supremacy expert and professor of modern American history at the University of Sussex. “[They] don’t seem to understand how the far right operates.”

Facebook defines white supremacists as those who believe the white race is superior and should dominate other races, according to training documents first published by Motherboard.

White nationalists, the materials state, seek to “develop and maintain a white identity” and “ensure the survival of the white race". White separatism is defined as a “slightly more extreme version of white nationalism,” that seeks to create “white-only states”. The company claims these ideologies don’t “seem to always be associated with racism (at least not explicitly)”.

This is in contrast to a definition from the Anti-Defamation League – a leading non-governmental organisation fighting antisemitism and hate – which identifies white nationalism as a euphemism for white supremacy created by white supremacists.

A Facebook spokesperson told The Independent that the policies in the Motherboard article were accurate, though some were outdated. The distinction between white nationalism and white supremacy still stands, she said.

The spokesperson said Facebook had consulted with multiple academics and non-governmental organisations when creating the policy. These experts, she said, emphasised the distinction between the white supremacist desire to dominate and the white nationalist desire to segregate by race.

But Mr Webb said these distinctions meant little in practice. While white supremacists may be explicit in their racism – burning crosses or physically attacking racial minorities – these same beliefs are implicit in a white nationalist credo.

“The implicit assumption is that there can be no commingling of black and white, or Jew and Christian,” Mr Webb explained. “And the reason for that is that those people are deemed to be inferior”.

Indeed, one white nationalist Facebook page is known as “Faith and Heritage” has posted repeatedly in defence of slavery. Comments on the page “Stop Islamization of the World” called Indian people “desert rats” and “uncivilised,” and claimed they “DO NOT FIT in our world”.

“Roundup and shoot,” one user wrote under a video of protesters in Maharashtra.

A Facebook fan page for Mr Kessler encouraged people to attend a second Unite the Right rally, despite Facebook’s policy prohibiting users from promoting white supremacist events. Participants at last year’s rally carried tiki torches and Confederate flags, and chanted “Jews will not replace us”. One woman was killed when a car ploughed through a crowd of counter-protesters.

The Facebook spokesperson said any expression of white nationalism would be deleted if coupled with content violating Facebook's rules against hate speech. The posts in question would likely be in violation of those rules, she said, but they had not been removed by the time of publication.

Still, Mr Webb said that by simply allowing these groups to exist – and to distinguish themselves from more widely condemned white supremacists – Facebook was essentially “playing the game for them”.

“White nationalism has been a mechanism by which racists have attempted to cloak their political beliefs with a layer of respectability, and to move themselves out of the margins and into the political mainstream,” he said.

“By complying with the self definition that racists are using,” he added, “Facebook is in danger of actually facilitate racists in that process.”

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