This Valentine’s Day marks a year since seventeen people were killed in a shooting at Marjory Stoneman Douglas High School, in Parkland, Florida. On February 14th, the Web site and social-media feeds of the March for Our Lives, the youth-led gun-control movement that began in the aftermath of the shooting, will go dark. The founders of the movement will not give interviews or make any public comments.

“It’s about recognizing that we need to take time for ourselves because we’ve been going so strongly for the past year without a breather,” Jaclyn Corin, a senior at Stoneman Douglas and one of the co-founders of the movement, told me in a recent phone call. “We’re giving ourselves that time to be with our friends and our family.”

Last year, on February 15th, I travelled to Parkland to cover the tragedy and was surprised to find myself also documenting the rise of a political movement. Along with the rest of the country, I watched as Sarah Chadwick, Cameron Kasky, Delaney Tarr, David Hogg, and their classmates addressed the media and lawmakers with a controlled fury and eloquence made more potent by their youth. Three days later, I attended a rally organized by the Broward County school board in nearby Fort Lauderdale, where a Parkland senior named Emma González made what seems to be the first speech with national resonance by a member of her generation.

Her concluding refrain, “We Call B.S.,” has been printed on buttons and painted on signs. It’s easy to forget how spontaneous it was, written from a place of raw emotion and delivered with urgency by someone with a preternatural rhetorical talent. It was also informed by being a member of a generation that has had to train for school shootings for years. As González said that day, “The students at this school have been having debates on guns for what feels like our entire lives.”

From the beginning, what made the March for Our Lives students seem different was the simple fact that they believed that the worsening epidemic of gun violence in this country could actually be fixed. Only days after the shooting, they directly lobbied representatives in the Florida state capital of Tallahassee and in Washington, D.C. On March 14, 2018, to commemorate a month since the event and to advocate for stricter gun laws, they led more than a million students to walk out of schools across the country. On March 24th, hundreds of thousands of people rallied outside the Capitol for the March for Our Lives, the largest youth protest in Washington since the Vietnam War. Another walkout followed, on April 20th, the nineteenth anniversary of the shooting at Columbine High School, in Littleton, Colorado.

The protest phase of the movement mostly ended there, but the young activists continued their work. They organized two bus tours to encourage young people to vote, one in Florida and one that toured nationwide, and registered thousands of young voters over the summer. They held public meetings and formed alliances with other local youth gun-control activists—Good Kids Mad City and the Peace Warriors—and survivors of mass shootings in Santa Fe, Texas; Aurora, Colorado; and the Red Lake Indian Reservation, in Northern Minnesota, among many other places. They showed their commitment not only to ending mass shootings but to educating the public on the ways that guns increase the likelihood of fatality in acts of suicide, domestic violence, and gang strife. During a fall college tour, they continued their voter-registration push, partnering with Rock the Vote and the N.A.A.C.P.

Previously, mass shootings had been met with collective mourning followed by inaction. The students condemned the inertia. They perfected the art of puncturing the N.R.A.’s attacks on proposals like universal background checks and banning assault rifles. They encouraged voters to see gun violence not as some kind of natural disaster but as rooted in policy decisions made by elected officials who should be held responsible. Fixing the problem would require the will of the people with power. The students asked, rightly: Where was the will? Why were adults so inept at protecting their children?

The March for Our Lives students marked the beginning of a year of youth activism, but it would be a mistake to say that they ignited it. Youth activism had been growing for several years: United We Dream, the youth-led immigrant organization that advocated for the DREAM act and occupied the halls of Congress last spring, was founded in 2008; the anti-racism and anti-police-violence movement Black Lives Matter, which has since grown into the Movement for Black Lives, started in 2013. Young people who worked for Bernie Sanders’s 2016 Presidential campaign went on to revive the Democratic Socialists of America as a political force and, in some cases, ran for office themselves. The Sunrise Movement, the youth-led climate-change-advocacy group that has helped put the proposal for a Green New Deal on the Democratic policy agenda, started in late 2017. And, as the Parkland students discovered when they began their work, there was already a network of youth activists working to end the epidemic of gun violence.

A lot of this work coalesced in the 2018 midterms, which were seen even by nonpartisan organizations like March for Our Lives as an opportunity to question the complacency of Congress, where the reëlection rate has traditionally been about ninety per cent. Young former Bernie Sanders staffers started the political-action committee Brand New Congress with the intention of reviving a primary election cycle that in many districts was merely symbolic. Brand New Congress recruited a dozen candidates. One actually won her election: Alexandria Ocasio-Cortez. By that time, the group had merged with Justice Democrats, a political-action committee that supported the candidacies of Ocasio-Cortez, Ayanna Pressley, Ilhan Omar, and Rashida Tlaib. All of these groups emphasized youth-voter turnout—and an estimated thirty-one per cent of eligible voters between the ages of nineteen and twenty-nine turned out in the 2018 elections. The Center for Information and Research on Civic Learning & Engagement, out of Tufts University, reported that that number, as low as it is, represented the highest youth turnout in a midterm election since 1982.

The Green New Deal, gun control, and Medicare for All are now seen as central issues in the 2020 Presidential primaries, but March for Our Lives has chosen to advocate for issues rather than individual candidates. Along with groups like Moms Demand Action and Everytown for Gun Safety, March for Our Lives can claim credit for changing laws. In 2018, according to the Giffords Law Center to Prevent Gun Violence, sixty-seven gun-safety bills were signed into law in twenty-six states and Washington, D.C. On February 6th, March for Our Lives founders joined the parents of slain Stoneman Douglas students at the first House hearings on gun violence in eight years.

As the Parkland students and others from their generation have shown, there is much political momentum to be gained simply by describing what is wrong with greater urgency: a broken health-insurance system; several generations who collectively owe more than one and a half trillion dollars in student loans; the existential threats of climate change, gun violence, police violence, stagnant wages, and widening inequality. But, unlike previous generations of youth activists, the ones today are eager to work within the existing political processes. Asked if a year of close scrutiny of electoral politics had left him disillusioned, Matt Deitsch, one of the March for Our Lives co-founders, told me that it had not. “It’s not about being disillusioned, it’s about being upset.” He quoted Marjory Stoneman Douglas, the namesake of his alma mater, who was an advocate for the preservation of the Everglades: “Be a nuisance when it counts.”