The first weeks of school should be filled with jitters, anticipation and fresh starts. Instead, in Evergreen, Colo., they were filled with grief and fear. A 16-year-old opened fire at Evergreen High School, wounding two classmates before turning the gun on himself.
Deadly school shootings in the U.S. are tragically common, but they are not inevitable. The 16-year-old who opened fire on his classmates and ultimately took his own life had been exposed to a toxic online community, including a forum in which graphic violent videos and extremism were celebrated.
Our team of analysts has found that at least two other school shooters in the past year were active in similar online spaces. The teenagers who perpetuated attacks at the Abundant Life Christian School in Wisconsin and Antioch High in Tennessee were both steeped in online spaces that glorify violence and amplify extremist narratives. Meanwhile, the perpetrator of the Annunciation Catholic School shooting in Minnesota used names, symbols and phrases that likely originate in such spaces.
Moreover, these teens even referenced one another as inspirations for their own successive attacks.
Today’s school shooters are often driven by a broader online nihilism, finding validation in digital subcultures that glorify violence and fuel a cycle of imitation. We must broaden our understanding of extremism. Today’s deadly attacks are fueled not by ideology alone, but by the toxic glorification of mass violence itself.
One particular gore forum in which these three recent school shooters were active briefly crashed due to a surge in traffic after Charlie Kirk’s death. Nearly half of young Americans aged 13 to 17 report being online “constantly,” and increasingly, they’re encountering spaces that encourage them to celebrate and perpetrate violent acts. We are living with the unthinkable: children killing children. Again and again, these deadly attacks are fueled by digital ecosystems that normalize hate, idolize mass shootings and turn violence into spectacle.
Months before his attack, the Evergreen shooter immersed himself in extremist and gore-filled online forums. He posted antisemitic and white supremacist views, consumed content glorifying violence, and adorned tactical gear he acquired with extremist symbols. He emulated previous killers, including the Wisconsin shooter last December and the Columbine shooters, signaling the deadly inspiration these online spaces provide.
The Evergreen shooter was active on a forum where users share graphic videos of murder, rape, suicide, beheadings and animal abuse. In less than a year, he became the third teenager linked to that platform who went on to carry out a school shooting or murder. He actually joined it during the narrow window between the Wisconsin and Tennessee attacks.
In a now-deleted TikTok video, the Evergreen shooter modelled a tactical helmet and a gas mask, and the song that Brenton Tarrant livestreamed the 2019 Christchurch Mosque shootings to playing in the background. This is a pattern, not a coincidence.
For years, violent extremism was seen as ideologically driven — organized groups, manifestos, propaganda. But today the threat is shifting. Teens are not only being driven into political or religious extremism. Increasingly, they are being inspired by violence itself.
The online tactics that were once the primary domain of extremists have become a model for a new generation of school shooters.
In some online communities, mass shootings are celebrated as accomplishments. Perpetrators are elevated as icons. Violence is stripped of ideology and exalted as an end in itself.
This toxic convergence of extremist content and glorified violence demands urgent action. Mainstream internet infrastructure networks, like Cloudflare, provide the infrastructure that keeps these sites online, allowing young people to venture ever deeper into violence and extremism.
What happens in these online spaces does not stay there. It spills into classrooms, neighborhoods and families. A teenager up late scrolling can stumble into communities where brutality is normalized, memes mock empathy and peers encourage each other to commit atrocities.
These aren’t obscure websites anymore. They hide in plain sight, exploiting algorithms, anonymity and humor to lure in the vulnerable and curious alike.
Policymakers, tech companies, educators and parents must confront this crisis with urgency because all signs point to this happening again. That means demanding greater accountability from online platforms and networks that allow these ecosystems of violence to flourish. It also means equipping schools and families with resources to spot early warning signs.
Over the years, my team has helped stop extremists and antisemites in their tracks — sometimes by working with law enforcement to prevent attacks, other times by ensuring perpetrators are held accountable. But the truth is, we can’t be everywhere at once. And every time an incident slips through — or, as with the Evergreen shooter, when we flag content to law enforcement but the attack still happens — it hits hard. Those moments are gutting. Yet those moments don’t weaken our resolve; they deepen it. They remind us why our mission matters and why the work is far from done. They remind us that the threat is real, the stakes are human lives, and our mission is far from finished.
The tragedy in Colorado — and those in Wisconsin, Tennessee and Minnesota — must not fade into the endless churn of forgotten news alerts. They should galvanize us to act.
We still have a choice. The next generation is growing up in an online world that can either connect and uplift or radicalize and destroy. The path we take will determine whether we prevent the next tragedy or simply wait for it to happen again.
Oren Segal, of the ADL Center on Extremism, is senior vice president of Counter-Extremism and Intelligence at the Anti-Defamation League.
