Before the massacre in Christchurch, New Zealand, in which 49 people were murdered at Friday prayers at two mosques, a man who identified himself as Brenton Tarrant posted notice of his intention to live-stream an “attack” on 8chan, the notorious online messageboard.

It opened with jokey, ironic lingo. “Well lads, it’s time to stop shitposting and time to make a real life effort post … It’s been a long ride and despite all your rampant faggotry, fecklessness and degeneracy, you are all top blokes and the best bunch of cobbers a man could ask for.”

The tone of the post, the “Aussie shitposter” avatar used (a running, jokey meme concerning Australian banter, popularised on 4chan, another messageboard), and the manifesto appear to make this basic political orientation obvious to anyone who has watched the online subculture of fascism proliferate over recent years.

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Does it bear a hallmark of an Islamophobic white nationalist – perhaps one who has been radicalised online by the “ironic”, chan-driven culture of the new global fascism?

This new style of fascism proselytises online, attempts to “redpill” white men using the plausible deniability afforded by irony, and then immerses recruits in an online movement culture built on memes, pseudoscientific dogma, racial panic and the worst of internet culture.

A leaked style guide from what may be the most read neo-Nazi website in history, the Daily Stormer, suggests irony is deliberately cultivated as a way of drawing people into the far right, step by step.

The video live-stream of the killings tries to situate the terrible violence in a framework of irony, with references to subscribing to video game commentator PewdiePie, the game Fortnite, and a propaganda song performed by Bosnian Serb soldiers in the 1990s.

This same style of “ironic” fascism has been exposed in countless leaks of white nationalist and neo-Nazi chats in the United States. It’s the same culture that has been on display in street violence from Charlottesville, Virginia, to Portland, Oregon, where protesters have come to violent street fights dressed as Pepe the Frog.

The now-scrubbed Twitter account returned incessantly to white nationalist obsessions, for example the idea of “The Great Replacement”, also the title of the manifesto. White nationalists often hold that declining birthrates among culturally “degenerate” whites, and the influx of non-white immigrants, represents a process of so-called “white genocide”. The only possible response, in the view of many of them, is authoritarianism and violence.

The gun shown in the live-stream video featured references to historical figures who, in the eyes of white nationalists, fought against encroachments into Europe by Muslims – like Charles Martel, who beat the forces of the Umayyad Caliphate at the Battle of Tours, or Josué Estébanez, who murdered the antifascist Carlos Palomino in the Madrid Metro in 2007.

These civilisational obsessions are shared by a global Islamophobic movement that goes beyond the fringes of white nationalism. Similar strains of Islamophobia can be found in institutions which have significant purchase on conservative politics.

The manifesto is said to have also paid fealty to previous mass murders. The final 8chan post is headed with the slogan “screw your optics”, a phrase that appeared in the final Gab post of Robert Bowers, who allegedly murdered 11 Jews at the Tree of Life Synagogue in Pittsburgh, Pennsylvania, last October. Bowers has pleaded not guilty.

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The manifesto’s focus on a grand historical drama of resistance to Islamic invasion of white homelands appears reminiscent of the manifesto of Norwegian mass murderer Anders Breivik.

The post is said to also express admiration for Dylann Roof, who killed nine people in Charleston, South Carolina, in 2015, and who has attracted an online fandom who jokily refer to themselves as the “Bowl Gang”, after the killer’s haircut.

The juxtaposition of remorseless murder, jokey commentary and memes in one of the most terrible livestreams in history appears utterly representative of the violent culture of radicalisation.

This is the most dangerous political current in the contemporary world. We must confront it, urgently.

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