They are seen as the shock troops of a burgeoning direct-action environmental movement. Earlier this year, members of Extinction Rebellion brought the center of London and some other major British towns to a standstill by barricading bridges, standing on top of trains, and blocking major thoroughfares and crossroads.
Extinction Rebellion (XR), a campaign of civil disobedience born in Britain and aiming to address a worldwide climate crisis, has been endorsed by Swedish climate activist Greta Thunberg, the teenage poster child of environmentalism. XR has pledged to cause more disruption, arguing that governments are not doing enough to stop the "climate emergency."
The group, which is spawning similar campaigns in the United States and Australia, says climate activists have no choice but to take matters into their own hands. It demands that governments prevent further biodiversity loss and commit to producing net-zero greenhouse gases by 2025. Otherwise, XR says, there will be a mass extinction of life forms on the planet within the lifetimes of the demonstrators themselves.
The group's next target is next month's star-studded London Fashion Week. Activists have promised to shut down the five-day runway event in a bid to raise awareness of the environmental damage caused by the fashion industry.
"We need to change our culture around consumption," said climate activist Bel Jacobs. "People have no idea how environmentally destructive fashion is."
Greenhouse gas emissions from making textiles was estimated at 1.2 billion tons of CO2-equivalent in 2015, more than all international flights and maritime shipping combined, according to the Ellen MacArthur Foundation, a British environmental charity.
XR's actions have been applauded by many environmentalists, who say the only way to make governments, people and corporations sit up and take climate action is to shock them into it. But the radical philosophy underpinning the group, which includes wanting to set up citizens' assemblies that could overrule parliament, is drawing increasing criticism from foes, who compare the group to a millenarian sect.
"The cultish nature of XR's activities is a little spooky," said Austin Williams, director of the Future Cities Project, a group that focuses on urban planning and futurist technological solutions.
Sympathizers acknowledge that XR hasn't helped itself with some of the remarks made by its leaders. Co-founder Gail Bradbrook said her realization that humanity was on the brink of extinction came from taking huge doses of psychedelic drugs, which "rewired" her brain and gave her the "codes of social change."
Roger Hallam, another co-founder, has said, "We are going to force the governments to act. And if they don't, we will bring them down and create a democracy fit for purpose. And yes, some may die in the process."
Hallam is not a scientist but has a track record as a political activist, and holds a Ph.D. on "digitally enhanced political resistance and empowerment strategies."
Several leading XR adherents have announced they've decided not to procreate in response to the coming "climate breakdown and civilization collapse," arguing the world is too horrible a place to bring children into it.
The BirthStrikers, as they are nicknamed, received some endorsement earlier this year from U.S. Congresswoman Alexandria Ocasio-Cortez, who said the climate emergency "does lead young people to have a legitimate question — 'Is it OK still to have children?'"
XR critics have compared the BirthStrikers to the Cathars, a medieval religious sect that encouraged celibacy and discouraged marriage on the grounds that every person born was just another poor soul trapped by the devil in a body.
XR has also seen defections. Sherrie Yeomans, coordinator of XR blockades in the English city of Bristol, left the group, saying, "I can no longer surround myself with the toxic, manipulative Extinction Rebellion cult."
Johan Norberg, a Swedish author, historian and XR critic, worries that the group is fueling anxiety while not being practical about the possible solutions to global warming.
"I guess it depends on your definition of cult," he said. "But I think it is a growing, but very radical, sentiment that I fear plays a part in giving people anxiety about their life choices, and also leads us to thinking about these things in the wrong way," he told VOA.
On the BirthStrikers he said: "The bizarre thing is that they just think of another human being as a burden, a mouth to feed. But they also come along with a brain to think, and hands to work. I don't know what scientific insight and which technology will save us from not just global warming but also the many other problems that will affect us — the next pandemic, natural disaster and so on — but I know that the chance that we'll find it is greater if we have more people alive, who live longer lives than ever, get a longer education than ever, and are more free to make use of the accumulated knowledge and technology of mankind to take on those problems."
Norberg points to a future of "electric cars and, soon, planes," and biofuels made from algae and extraction of CO2 from the atmosphere. He worries about the economic consequences if the abrupt zero-growth goals of XR were adopted.
"It would result in a reversal of the amazing economic development that has resulted in the fastest reduction of poverty in history. A lack of growth and international trade would result in human tragedies on a massive scale," he said.
XR's co-founders say Norberg's formula won't halt climate change and stop extinction. They defended themselves against critics' cult charges, arguing recently in an article in a British newspaper, "We've made many mistakes, but now is the time for collective action, not recriminations."
"Extinction Rebellion is humbly following in the tradition of Gandhi and Martin Luther King," Hallam said. "After covering basic material needs, human beings are not made happier through consuming more stuff."
Bradbrook told reporters in London, "We oppose a system that generates huge wealth through astonishing innovation but is fatally unable to distribute fairly and provide universal access to its spoils. ... We need a 'revolution' in consciousness to overturn the system."