It’s been a year since teenage Swedish climate protester Greta Thunberg began her solitary school strike outside the Parliament building in Stockholm. The New Yorker’s Masha Gessen profiled her in October 2018, and that’s when I first heard of her: her trademark braids framing a round face, her depression and Asperger’s diagnoses, how she’d convinced her opera-singer mom to stop flying and her family to go “mostly” vegan. Since last fall, she’s given several unrelenting speeches excoriating powerful adults (at Davos, at the United Nations’ COP24 climate talks, in the British Parliament), been nominated for the Nobel Peace Prize, and fueled a new wave of teenage climate activism. She’s also become a major target of the global right wing—a sign, perhaps, that what she’s doing is working.

But even as I’ve watched her rise, and felt personally inspired by her message, I haven’t been able to figure one thing out. Why has Thunberg been able to break through and become a catalyzing figure, when other young people have been pursuing climate activism? Why was it Greta who had her face made into a 50-foot mural on the side of a building in Britain? Why, for example, didn’t the plaintiffs in Juliana v. the United States, a 2015 lawsuit filed against the American government for its failure to ward off a future of climate chaos, become media darlings? Is it because, as Thunberg’s critics continuously suggest, the left loves a victim—especially (I might add) one who’s also an adorable Scandinavian in braids? Or were we simply ready, in 2019, to hear somebody be as blunt and urgent as we sometimes feel, about this huge problem we’ve been mostly ignoring?

She neatly refuses to participate in a common dynamic around children’s environmental activism, where grown-ups respond to young environmentalists by condescending to them.

For one thing, Thunberg’s history with climate depression—she has described these feelings as having been, at one point in time, debilitating—is familiar to a lot of people. It’s a part of her story that the global right uses to discredit her (saying she’s “deeply disturbed”). Yet this narrative of being paralyzed by climate fears, before discovering that activism could be an outlet for them, is one of the biggest sources of her appeal. If you are a person in the United States who is not yet directly affected by climate-stoked storms or fires or drought but who accepts the scientific consensus and follows the news, you have possibly experienced a pattern of climate anxiety that looks something like mine—occasional four-hour panics when I think we are doomed fools living through the last good time, bracketed by longer periods when denial allows me to conduct the business of daily life. Perhaps because of her age, or perhaps because of the way her brain works, Thunberg doesn’t get those soothing periods of denial. She experiences only the intense dread. In her speeches, she channels that fact, recalling to sympathetic listeners the urgency of their own 3 a.m. fears. I think her approach is working on us because Thunberg’s climate depression isn’t an aberration—it’s an increasingly common collective sentiment.

Another part of Thunberg’s appeal: She doesn’t allow adult leaders to buy her off with promises, sweet words, or decorations. She neatly refuses to participate in a common dynamic around children’s environmental activism, where grown-ups respond to young environmentalists by condescending to them—poster contests, token inclusion in decision-making, TV shows and plastic toys aimed at “nature-loving” kids. Too easily, kids’ environmental instincts seem to get diverted into small projects they can do to “make a difference.” Thunberg doesn’t allow for that. She also lives her life with a profound attention—she refused a nomination for the Children’s Climate Prize, for example, because the finalists would have to travel by plane to the ceremony. These kinds of actions help demonstrate just how serious she is.

Thunberg wants big change. She’s not willing to be placated. And she’s found that her methodology works. “I made them feel guilty,” she said of her successful campaign to get her parents to quit flying and eating meat. (“It’s like you’ve killed 80 people!” she said to her mother once, when she came back from a gig in Japan.) “You say you love your children above all else, and yet you’re stealing their future before their very eyes,” she said at the U.N.’s Climate Change Conference, in December of 2018.

Many of us have been conditioned to respond to a person like Thunberg, who lives a life of rigid adherence to her own morals, with annoyance. We deploy logic to excuse our behavior. Sure, flights are bad, it’s easy to think, but the planes are still flying; me not buying a ticket isn’t going to help. Besides, anything I can do in my own life will change nothing, so long as governments and corporations aren’t on board with the cause. And yet, there’s a good argument to be made that living one’s values matters because doing so helps us remember to advocate for the kind of systemic change we need.

In my own life, the “Greta effect” has resulted in me finally eliminating meat from my family’s weekly household menu, after years of meaning to do so. We don’t have flight shaming in the United States, quite yet, but I don’t think I’m alone in beginning to suspect that our years of thoughtless tourism and guilt-free conference attendance may be drawing to a close. It’s impossible to say how much of this sea change may be attributable to Thunberg’s public refusal to fly, but her uncompromising approach aligns with the way that many of us are feeling.

This is one of the things that the right hates about Thunberg: She shames grown people—for flying, for driving, for profiting off things that are undermining the planet’s future. The undercurrent of much conservative Greta hate is a feeling that authority is askew in this case: “Why are adults listening to this nagging girl?” Part of that is misogyny. As Martin Gelin pointed out in the New Republic recently, researchers have found no small amount of woman-hating threaded through the backlash against climate activism. Environmentalism has long been culturally coded as feminine—come back, Teddy Roosevelt!—and people reluctant to sacrifice their personal pleasures for climate stability may, when confronted by someone like Alexandria Ocasio-Cortez or Greta Thunberg, feel oppressively corrected.

I’d add to this very true observation about gender dynamics the fact that teenage activism, especially the kind that calls adults on the carpet the way Thunberg’s does, triggers conservatives who tend to hold a stronger belief in a hierarchal family model. Why, these critics ask, should I listen to what a young person wants? This feeling, blown up in scale, might be recognizable as the lack of consideration for future generations that allows deniers and delayers to mentally resist any action on climate. In contrast, on the left, many (not all) believe that parenting—or, just living in a world with young people—can also be about learning from these whippersnappers, being fueled by their enthusiasms, finding yourself reinvigorated by their fresh regard of things you’ve long known. In the story of Thunberg’s appeal to her parents, and the subsequent transformation of their lives, conservatives may see a relationship out of balance. I, on the other hand, recognize a family that feels both familiar and aspirational.

There’s one more timeworn conservative response to Thunberg’s activism: “The parents, or some other professional adult activist, must be telling her what to say.” This is an argument that, as I wrote last year when the right started saying the same about the Parkland kids, has been used against youth activism at least since children demonstrated with Martin Luther King Jr. It neatly sidesteps the social taboo on criticizing children in public by blaming their parents instead. In Thunberg’s case, concern trolls have professed themselves to be “worried” about her mental health, calling her a “child sacrifice” and a “puppet.” In fact, climate deniers have long argued that children shouldn’t be taught climate change because it scares them too much. (One U.K. blog, Climate Lessons, has been collecting news stories of children being terrified after learning about climate change in schools since 2010, and has, in the past year or so, been relentlessly focused on Thunberg.)

I suspect that deniers and delayers don’t resist climate education and youth climate activism simply out of protectiveness toward children. Researchers from North Carolina State University found, in a study published this year, that educating middle school children about climate change led to increased concern on the issue from their parents. “We … found that the results were most pronounced for three groups: conservative parents, parents of daughters, and fathers,” one of the researchers said. Another added: “[Children] seem to help people critically consider ways in which being concerned about climate change may be in line with their values.”

I think this is the real reason Thunberg’s message hits so hard, on both the right and left. She scares the right because it can see that we adults are taking her seriously. She transfixes the left because she helps activists focus on the misalignment between what we believe and what we do. “Some people say that the climate crisis is something we have all created, but that is not true,” Thunberg said at Davos, speaking to the wealthiest people in the world. “Because if everyone is guilty then no one is to blame, and someone is to blame … I think many of you here today belong to that group of people.” In 2019, we were finally ready to hear that blunt message, and move forward.