Robert F Kennedy Jr has mass appeal despite his extreme ideas. This theory explains why | Darren Loucaides

“Back at home in the United States, the newspapers are saying that I came here today to speak to about 5,000 Nazis,” Robert F Kennedy Jr told a large crowd in Berlin. Estimated at 38,000 people, the crowd was a mix of hippies, anti-war types, Green party voters and anti-vaxxers, rubbing shoulders with a smattering of skinheads. It was late August 2020 and a group called Querdenken had rallied this motley crew together in defiance of Covid-19 restrictions.

“Governments love pandemics,” Kennedy said. “They love pandemics for the same reason they love war – it gives them the ability to impose controls that the population would otherwise never accept.”

Last month, in Senate confirmation hearings for his appointment as the US secretary of health and human services, Kennedy was questioned on having previously compared the Center for Disease Control’s work to that of “Nazi death camps”, calling Covid-19 a bioweapon genetically engineered to target black and white people while sparing Ashkenazi Jews and Chinese people, and blaming school shootings on antidepressants. “He has made it his life’s work to sow doubt and discourage parents from getting their kids life-saving vaccines,” said the Democratic senator Ron Wyden. “It has been lucrative for him and put him on the verge of immense power.”

Kennedy has gone from courting the conspiratorial fringes of the internet to the halls of the White House. He could be confirmed within days. With hindsight, the Berlin speech he gave five years ago was the moment a dangerous new political phenomenon went global. It’s called diagonalism.

Coined by the political theorist William Callison and the historian Quinn Slobodian, diagonalism describes the union of disparate groups across the political spectrum around a suspicion of all power being involved in conspiracy. Diagonal movements see big tech, big pharma, banks, climate science and traditional media as accomplices in totalitarianism, evidenced by Covid mandates through to innocuous intergovernmental proposals such as the “great reset” and 15-minute cities.

For diagonalists, the control of electoral processes by powerful interests means that governments are de facto illegitimate. And so they advocate for distributed power – not to empower any community, but the individual. By definition they are susceptible to far-right radicalisation. Callison and Slobodian trace their use of the term back to Querdenken – which roughly translates as “lateral thinkers” – the group that organised the Berlin rally addressed by Kennedy.

Kennedy recalled his uncle’s visit to the same city decades earlier, even repeating the historic line “Ich bin ein Berliner”. “And today again, Berlin is the frontline against global totalitarianism,” he said, before working through a bingo card of conspiracy theories. An extended “quote” Kennedy read from Hermann Göring’s testimony at the Nuremberg trials, including that “the only thing a government needs to make people into slaves is fear”, was copy and pasted across social media for months afterwards – even though there is no record of Göring saying those words.

But Kennedy’s Berlin speech and the Querdenken rally itself were not merely notable for the controversy they caused. In drawing together veterans of anti-war and anti-globalist groups alongside health influencers, environmentalists and the far right, Querdenken became the blueprint for diagonal movements. Through its anti-power conspiratorial framing and the mirroring of methods used by decentralised grassroots movements, Querdenken was able to draw diagonal lines across pre-existing political allegiances, cultural divides and single issues, such as the climate or vaccines, to forge a mass coalition of support. Kennedy himself epitomises this new coalition – one that was nascent at the time, but is now at the heart of Trumpism.

As a former environmental lawyer, Kennedy spoke with eloquence and passion in the past about corporations contaminating rivers and polluting the skies, the plight of asthma especially afflicting black people, and the existential threat of the climate crisis. In the Berlin speech, Kennedy mingled conspiracy theories with genuine concerns and anxieties held by the public. He said he saw “people who want leaders who are not going to lie to them, people who want leaders who will not make up arbitrary rules and regulations to orchestrate the obedience of the population. We want health officials who don’t have financial entanglements with the pharmaceutical industry, who are working for us and not big pharma.”

In her book Doppelganger, Naomi Klein writes powerfully on how diagonal movements and influencers often identify real issues that progressives had grown timid about – the sway of oligarchical wealth over politics, the rise of digital surveillance, the impact of rampant capitalism on our mental and physical health. But instead of articulating the actual causes or plausible solutions, they have constructed bogus metanarratives. Rather than increasingly antidemocratic billionaires, it was an organised cabal of global elites, unaccountable deep-state bureaucrats who secretly ran the world – or, at the furthest end, blood-sucking satanists, as QAnon followers believed. A mirrorworld had emerged. And it is demagogues such as Trump who have benefited.

“Despite claims of post-partisanship, it is right-wing, often far-right, political parties around the world that have managed to absorb the unruly passions and energy of diagonalism,” says Klein, “folding its Covid-era grievances into preexisting projects opposing ‘wokeness’ and drumming up fears of migrant ‘invasions’. Still, it is important for these movements to present themselves (and to believe themselves to be) ruptures with politics-as-usual; to claim to be something new, beyond traditional left-right poles.”

While the crowd that listened to Kennedy’s speech that day in 2020 was a heterogeneous mix, a few miles away, a mob of far-right activists and QAnon supporters tried to storm the Reichstag, home to Germany’s parliament, after one of their number falsely announced Trump was in Berlin to liberate the country. The violent scenes would be replicated in the more deadly assault on the Capitol on 6 January 2021. This was the extreme end of diagonalism exploding into life. (An investigation I led into Covid-sceptic groups found that by then, Querdenken and others had become obsessed with Trump – and gravely radicalised.)

If Robert F Kennedy Jr is confirmed to Trump’s cabinet, a once-staunch environmentalist and defender of women’s reproductive rights turned conspiracy theorist and super-spreader of health misinformation will dictate health policy in the US. Diagonalism has ascended to the pinnacle of global power. The mirrorworld is becoming our reality.

• Darren Loucaides is a writer based in Barcelona and London

• Do you have an opinion on the issues raised in this article? If you would like to submit a response of up to 300 words by email to be considered for publication in our letters section, please click here.