In New York, they doused the Wall Street bull with fake blood. In Toronto, they occupied a major viaduct. Self-described “rebels” barricaded themselves into a Paris shopping mall and blocked the Westminster Bridge in London. The goal of these acts of civil disobedience? To recruit hundreds of thousands of people—if not millions—into the climate movement.

Monday’s events marked the beginning of a week of action from the Extinction Rebellion (XR) activist group, which urged its members and supporters to get arrested by staging flashy protests that interfere with the day-to-day functioning of dozens of cities around the world.

The group’s strategy hinges on a critical figure: mobilizing 3.5 percent of the population in a given country, which has been repeatedly proven to be a threshold for systemic political change. In this case, members of XR want governments to accede to a key demand: creating a citizen’s assembly that accelerates society away from climate-destroying industries and towards a net-zero emissions economy by 2025, five years earlier even than the ambitious 2030 target at the center of Alexandria Ocasio-Cortez’s Green New Deal.

“That citizen’s assembly can make the really hard decisions that we recognize politicians are not able to do,” said Eve Mosher, a spokesperson for Extinction Rebellion New York, dozens of whose members were reportedly arrested on Monday.

If enough countries begin enacting radical economic change like this, we could cross a “global tipping point,” Mosher said, where remaining nations rush to take part in the shift, drastically and immediately shrinking global greenhouse gas emissions and potentially pulling human civilization back from the brink of ecological collapse.

This probably sounds like wishful thinking to the extreme. But XR’s strategy is drawn from serious academic research on nonviolent rebellion—in particular, a 2011 book called Why Civil Resistance Works by Erica Chenoweth and Maria J. Stephan, which analyzes nonviolent conflicts from 1900 to 2006 and concludes that overthrowing governments requires far fewer people and resources than you might assume. The revolution Mosher and other XR members envision is definitely unlikely, at least in today’s political environment, but experts contacted by VICE said that it fits within a long and often effective tradition of social movement-driven change.

So what is Extinction Rebellion anyway?

The activist group was officially launched by several British academics in October 2018 and quickly grabbed attention by blocking five London bridges and effectively bringing the city’s center to a standstill—an act of civil disobedience for which 85 people were arrested.

Whereas some larger environmental groups work within institutions to create policy change, XR operates on the assumption that our institutions are corrupted by corporate interests and thus must be confronted by a mass movement of ordinary people if we are to have any hope of averting civilization-destabilizing levels of global heating. “What you have to do is create a massive load of shit nonviolently,” XR’s co-founder Roger Hallam told VICE in July.

Despite several actions this summer in New York and Washington, D.C.—including activists literally gluing themselves to Capitol Hill and scaling the New York Times building—the group hasn’t really broken into the U.S. “We’re not as advanced in our movement building as the U.K.,” Mosher said. So while XR activists in London will be “seeking specifically to shut down the government” starting October 7, she said, their American counterparts will stage attention-grabbing actions like a “die-in” outside of the New York Stock Exchange, along with an Occupy-reminiscent “Rebel Fest” in Washington Square Park, that help make people aware of XR and potentially convince them to join.

Why you only need 3.5% of the population for a revolution

XR’s rationale for why these actions matter strategically is directly inspired by Why Civil Resistance Works, a 2011 book that transformed the study of non-violent rebellion. After researching more than a century’s worth of conflicts, authors Chenoweth and Stephan concluded that peaceful campaigns are twice as likely to succeed as armed ones. Part of the reason for that is participation—you need to be in good physical shape and properly trained to fight violently, which limits numbers, whereas almost anyone can join a mass protest.

The larger the social movement, the greater the chance its members will have some kind of family or personal link to military leaders, media publishers, businesspeople, and other elites. When enough elites, along with masses of ordinary people, withdraw their support from the ruling regime, it can no longer function. In all the successful rebellions that Chenoweth and Stephan studied, including the student-led overthrow of Serbian dictator Slobodan Milosevic in 2000 or the millions of Filipinos who in 1986 caused the repressive Marcos regime to fold, this tipping point came when 3.5 percent of the population became actively mobilized—and many campaigns succeeded with less.

But there are some important qualifiers

First of all, getting 3.5 percent of Americans (or nearly 11 million people) out in the streets demanding radical climate action would be no simple feat. “It’s also really important to remember that if you get 3.5 percent of the population, or around that amount, who are publicly organizing, that movement may have majority support in the rest of the population,” explained Hardy Merriman, president of the International Center on Nonviolent Conflict, which helped support and fund Chenoweth and Stephan’s research. “It’s sort of the tip of the iceberg that can be seen rather than saying, ‘well if we just get 3.5 percent support we’ll win.’ I think that would be a misinterpretation.”

And it’s not enough to simply get huge numbers for a single day—or week—of action, like what we saw in September for the Global Climate Strikes. Successful social movements require a steady escalation of events and actions. “If, like, in the White House one morning the cleaning ladies decide to stop cleaning the toilets then there is a huge impact,” explained Margherita Belgioioso, an assistant professor at the University of Kent who recently co-authored a paper with Chenoweth. “The more people you have out there, the more you impose these sorts of costs…the more likely are the nonviolent campaigns to be successful.”

Does it make sense for XR to apply these insights to climate change?

Though one of the top goals of XR New York is “mobilising 3.5 percent of the population to achieve system change,” the research behind this number comes from citizens overthrowing oppressive national governments, not a global fight to lower greenhouse gas emissions that doesn’t necessarily have clear heroes and villains.

“Sure the adversary is different [than fighting a dictator], sure the narrative is different, but the basic dynamics of civil resistance are the same,” Merriman said. There is an obvious injustice being committed (leaders failing to address or fix the climate emergency) and the institutional means of remedying that injustice (getting Congress to pass legislation) are broken, so ordinary people are coming together to challenge the entire system. In some ways XR has it easier than previous nonviolent campaigns, he said, which have had to confront “autocrats that are entrenched, that have the capacity for repression, the capacity to use violence, control of state media.”

But XR is still going up against a state apparatus that disproportionately targets people of color—a fact some observers argue that the group has yet to properly acknowledge. “White people in XR, however, assume that if they are polite and reasonable, the government will listen to them and protect them,” Tatiana Garavito and Nathan Thanki wrote for VICE last month. “Racialized communities and marginalized people know better.”

Mosher agreed it’s unreasonable to ask people already ill-treated by police, courts and the criminal justice system to voluntarily break the law starting on October 7, which is partly why XR New York is providing the option to mobilise lawfully in Washington Square Park: “We want those who can, to take arrests, while recognizing that there are many who cannot, for a variety of reasons, whether it’s health, age, socio-economic situation, the color of their skin.”