SIX MILLION

THAT’S ROUGHLY the number of students worldwide who skipped school to go on “climate strike” in 2019, in what marked the height of the climate movement before the pandemic chased it indoors.

And those millions, in turn, stand for everyone who built the biggest global movement of the millennium over the past decade, coming together across nations to demand action on climate change. They were as important to climate progress as the engineers who dropped the price of renewables.

It began slowly (I helped found 350.org, the first attempt at a grassroots global climate movement, in 2008) but accelerated as people around the world joined in — most often the leaders were indigenous activists and people already on the front lines of climate change, because they had the most at stake. Together, we fought pipelines and frack wells and coal ports, and built enough power that Barack Obama and other world leaders couldn’t come back from Paris empty-handed in 2015, unlike in 2009.

Young people were among the biggest leaders in the fight. You know Greta Thunberg, and you should. But she would be the first to say there are thousands of young leaders like her; in this country, they’ve included people like Varshini Prakash, whose advocacy of the Green New Deal through the Sunrise Movement helped transform U.S. politics. By 2020, thanks to a decade of mobilization, climate change broke through: Polls showed it near or at the top of Democratic-voter concerns. And so Biden named Prakash to a small team working on climate policy. Citizen pressure finally translated into legislative action when our first real climate bill, the Inflation Reduction Act, passed in August — 34 years and 45 days after climate scientist Jim Hansen first testified to Congress that global warming was underway. Which leads us to …