Hong Kong protesters gather at the Central District in Hong Kong.Adnan Abidi / Reuters

“A leader is best when people barely know he exists,” Lao Tzu, the ancient Chinese philosopher and founder of Taoism, is thought to have said. “When his work is done, his aim fulfilled, they will say: ‘We did it ourselves.’’’

But what if a leader doesn’t exist at all? Around the world, leaderless protest movements have emerged, drawing tens of thousands (and, in some cases, millions) of people to the streets. Though their catalysts vary, the protests have largely looked the same: From Hong Kong and Chile to Iraq and Lebanon, people have utilized social media to whip up spontaneous, mostly nonviolent grassroots demonstrations against their respective governments—efforts they have vowed to sustain until all their demands are met.

The movements have sometimes succeeded—unpopular legislation was reversed in some places, and public officials were forced to resign in others—but in a few instances that has only emboldened protesters to seek further demands. As the scale of government response intensifies, it raises the question: How long can these grassroots movements last? Without a clear organizer at the helm, do these protests risk morphing into something even its participants can’t control? Is the lack of centralized leadership a source of weakness—or strength?

In Chile, the protests have focused on inequality and corruption. In Lebanon and Iraq, the protests against the countries’ political systems have transcended sectarian lines. While some demonstrations erupted over specific grievances, such as proposed legislation in Indonesia to weaken the country’s anti-corruption agency and reduce the personal freedom of citizens, protests in Haiti, Egypt, and Bolivia have expanded beyond their original aims into calls for their governments to resign.

Even in places where authorities have acceded to some protesters’ demands, the demonstrations are still strong. In Hong Kong, the pro-democracy movement is in its sixth month, driven by widespread concerns about the city’s semiautonomous status and how long it can last. Despite the government’s withdrawal of the unpopular extradition bill that sparked the protest in the first place, the movement’s demands have only grown—and so, too, has the violence. Over the weekend, a barricaded university campus was the scene of some of the most intense clashes since the demonstrations began, as protesters launched archery arrows and Molotov cocktails in response to rubber bullets and tear gas from police. Though the Chinese government warned that further unrest would result in an “unimaginable and dreadful” future for the city, efforts to quell the protests, including mass arrests and a face-mask ban (a proscription that Hong Kong’s High Court ruled unlawful), have appeared only to buoy activists further.

In France, the similarly amorphous “yellow vest” movement has also proved its staying power. The national protests, which spiraled from grievances over rising fuel prices into a broader anti-government demonstration, celebrated its first anniversary on Sunday. Still, some things have changed. Though the spirit of revolt is still strong, the turnout has dwindled. And while most protests were initially peaceful, more violent elements have also emerged.

The leaderless nature of these protests isn’t incidental, nor is it unprecedented. “Before politics became populist, social movements became populist,” Paolo Gerbaudo, a political sociologist at King’s College London and the author of The Mask and the Flag: Populism, Citizenism and Global Protest, told me. He said the leaderless protests today are reminiscent of grassroots protests that began nearly a decade ago, from Occupy Wall Street of 2011 to the anti-austerity demonstrations in Greece and Spain that same year.

“These movements don’t appeal to specific categories,” he said. “They appeal to the entirety of the citizenry … who feel defrauded by the political class.”

The success of these protests can be attributed in large part to social media, which has enabled participants to communicate and organize in a more decentralized way. Whereas some have relied on encrypted messaging services such as Telegram, others use AirDrop, Apple’s fire-sharing function that lets users easily share content between devices. “Technology enables leaderlessness in a way that was not possible before,” Carne Ross, the executive director of Independent Diplomat, a diplomatic advisory group, and the author of The Leaderless Revolution: How Ordinary People Will Take Power and Change Politics in the 21st Century, told me. “Technology means you don’t need a leader to disseminate strategy. The strategy disseminates horizontally.”

It’s not just that social media has allowed these movements to bypass traditional top-down leadership. For many, the leaderless nature is the point. After all, appointing leaders makes it easier for governments “to focus on them, to pick them off, to arrest them, kill them, denigrate them,” Ross said. Leaderless protests, conversely, are more difficult to repress. Moreover, many of these protests are explicitly positioned against the concentration of power within a few hands. “By definition, these movements are going to be unsympathetic to any concentration of power within their own ranks.”

In Hong Kong, protesters have adopted as their rallying cry the martial artist Bruce Lee’s famous quote, “Be formless, shapeless, like water”—that is, to be impossible to suppress. In practice, this has manifested itself in a leaderless movement, known for forming spontaneous rallies, roadblocks, and sit-ins. In Catalonia, where thousands of people have railed against the Spanish Supreme Court’s October decision to jail nine Catalan separatist leaders, protesters paid tribute to Hong Kong by adopting some of their tactics, including staging a blockade of Barcelona’s airport.

But the lack of a leader is not without its flaws. France’s “yellow vest” movement experienced a split earlier this year between those who preferred to continue the demonstrations and those who sought to formalize it by standing candidates at the European elections (the latter effort ultimately failed). More recently, another schism has formed between those protesting peacefully and “black bloc” activists, who have deployed more violent methods, including vandalism and setting fire to motorcycles. Though the two groups are not formally related, their demonstrations have overlapped.

“In leaderless movements, there is of course a danger that minorities will use tactics that are not endorsed by the bulk of the protesters,” Ross said. Whether protests have leaders or not, authorities often crack down on demonstrations—but the lack of leaders may exacerbate tensions and violence when protesters have no one to provide direction on how to confront the authorities. Many of these confrontations have resulted in casualties. In Hong Kong, two deaths were recorded last week—the first to occur in nearly six months of demonstrations. In Lebanon, one protester was fatally shot by a soldier attempting to disperse the crowd. Elsewhere in the world, recent demonstrations have been considerably more deadly. In Chile, at least 20 people have been killed. In Iraq, the death toll has surpassed 300.

That many of these protests began as nonviolent movements may have played a crucial role in their longevity. But as the dynamics of these protests change—and as many of them incur more violence—is there a risk that they could unravel? When I put this question to Gerbaudo, he said protest movements “are by their very nature not sustainable in the long term,” in large part due to the amount of energy and commitment it takes to maintain them. Unlike official parties and organizations, “they don’t have the bureaucratic structures that would keep them going.”

For many protesters, though, the mind-set is simple: Don’t stop until all their demands are met. For those in Hong Kong, it’s expressed through the popular chant “Five demands, not one less.” In Lebanon, protesters have adopted the slogan “All of them means all of them,” in reference to their rejection of the entire political class.

Still, Gerbaudo argued that “we shouldn’t expect from social movements that which social movements cannot deliver,” noting that it’s not their job to solve the problems that spurred them. Rather, it’s “to raise questions that were not previously on the political agenda [and] to show that there is a large section of the population that doesn’t feel represented.”

In this way, at least, they’ve already succeeded.

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