For decades, law enforcement approached mass casualty violence through relatively familiar frameworks: the isolated extremist, the grievance-driven lone actor, the gang-affiliated retaliatory shooter, the ideologically motivated terrorist. Those frameworks still matter. But the recent attack at the Islamic Center of San Diego should force everyone in public safety to confront an uncomfortable reality: many investigators, policymakers and even experienced law enforcement professionals may still be underestimating how profoundly the ecosystem producing these attackers has evolved.
On May 18, two teenagers allegedly carried out a brutal attack outside the mosque, killing three people before taking their own lives. Early reporting pointed to familiar indicators: white supremacist imagery, accelerationist rhetoric, manifesto culture and references to prior mass shooters.
Investigators reportedly recovered Nazi iconography, propaganda materials, tactical gear and evidence of extensive online radicalization tied to the extremist ecosystem that emerged after the 2019 Christchurch mosque shootings and has influenced attackers across the globe for years.
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The danger of cumulative immersion
But stopping at the ideological label alone misses the deeper operational problem.
What law enforcement is increasingly confronting is not simply traditional extremism. It is an evolving digital underworld — decentralized, immersive and highly adaptive — where vulnerable young people are pulled into overlapping online subcultures blending nihilism, extremist propaganda, gamified violence, misogyny, accelerationism, meme warfare and social alienation into a self-reinforcing ecosystem.
These environments are often difficult to recognize from the outside because they camouflage themselves within what appears to be ordinary adolescent online behavior: gaming servers, meme pages, encrypted group chats, irony-driven humor, true crime obsession communities and fringe livestream channels. Inside these spaces, users communicate through layered jokes, coded references and constantly evolving language designed to evade detection by parents, educators and even investigators.
The danger is not always one single platform or one single ideology. It is cumulative immersion. A teenager may begin by consuming violent edgelord content ironically. Then comes exposure to nihilistic humor. Then conspiracy narratives. Then the glorification of prior attackers. Eventually, the individual is no longer simply consuming content. They are participating in an online culture that rewards emotional detachment, celebrates violence and treats mass casualty attacks as mythology.
That is part of what makes these investigations so difficult. Many of these young offenders do not fit the traditional organizational models law enforcement was trained to identify. They may never formally join an extremist group, attend meetings or communicate with a traditional handler. Instead, they exist inside fluid digital ecosystems where propaganda spreads socially rather than organizationally. In many cases, the radicalization process resembles social grooming more than classic recruitment.
The digital canon of mass attackers
What investigators have reportedly described as the “Sons of Tarrant” manifesto connected to the San Diego attackers illustrates how these ecosystems continue to evolve.
According to early reporting, the document combines elements of accelerationist white supremacy, incel grievance culture, antisemitic conspiracy narratives, admiration for previous mass killers and online meme aesthetics into a single piece of propaganda designed not only to explain the attack, but to inspire future imitators.
The references reportedly range from Elliot Rodger to Brenton Tarrant, Payton Gendron and other attackers whose manifestos and livestreams have become part of a circulating digital canon within these online spaces.
Two generations, two investigative worlds
As father and son writing this together, we admittedly approach the problem from different generations of investigative experience.
One of us comes from the old school of organized crime investigations, intelligence work and deep undercover operations. There was a time when reading graffiti on a wall, identifying new gang markings in a neighborhood or noticing who suddenly stopped showing up on a corner could tell you which crew was preparing for violence.
Street intelligence had texture. Human behavior left visible fingerprints.
The other grew up studying the online version of those same ecosystems, where the graffiti now exists in encrypted chats, meme culture, livestreams and algorithm-driven radicalization pipelines invisible to most adults. The symbols have changed. The terrain has changed. The velocity has changed.
More than once, our conversations have sounded like a debate between a retired street investigator and someone explaining a foreign language spoken entirely through memes and screenshots. But both perspectives matter.
Traditional investigative instincts remain critical because human behavior still produces warning signs. Radicalization still involves progression from grievance to identity formation to operational planning. But law enforcement must also recognize that today’s recruitment pipelines often operate inside digital environments that many agencies are still poorly equipped to navigate.
The operational reality is that some of these young people are effectively living double lives. To parents and teachers, they may appear socially awkward, isolated or chronically online. But inside these digital ecosystems, they are receiving validation, identity, status and belonging. They are being encouraged to see violence as a form of historic purpose.
Some are immersed for thousands of hours in communities where prior attackers are idolized, where manifestos circulate as ideological reference points and where livestreamed murder is discussed with the same casual familiarity previous generations reserved for sports highlights.
That should deeply concern every law enforcement executive in America.
What agencies need to do now
It also demands a broader mitigation strategy.
First, law enforcement agencies need significantly more training focused on digital subculture literacy and online radicalization ecosystems. This knowledge cannot remain confined to federal task forces or specialized intelligence units. Patrol supervisors, school resource officers, detectives and community policing personnel increasingly need baseline familiarity with the online environments shaping youth radicalization.
Second, fusion centers and behavioral threat assessment teams should expand beyond traditional ideological indicators and incorporate personnel familiar with accelerationist culture, incel ecosystems, extremist iconography and online platform migration patterns. These cases evolve rapidly across digital platforms, often moving from mainstream social media into encrypted or fringe communities long before violence occurs.
Third, partnerships between law enforcement, educators, mental health professionals and parents need to become far more proactive. Most parents simply do not understand the online environments their children navigate daily. That is not a criticism — the landscape evolves too quickly. Digital literacy now needs to become part of violence prevention in the same way drug awareness and gang awareness became essential in earlier generations.
Fourth, technology companies need to take more sustained enforcement action against networks that openly glorify mass casualty violence and circulate operational propaganda. Much of this ecosystem has existed in plain view for years. Researchers, journalists and investigators have repeatedly identified channels and communities tied to extremist accelerationism, yet enforcement often remains inconsistent and reactive.
Finally, law enforcement leadership must recognize that this threat environment is no longer solely about ideology. It is about vulnerable young people entering digital ecosystems that normalize dehumanization, reward grievance and gradually disconnect individuals from reality itself.
The next evolution of threat assessment
If policing adapted to organized crime, gangs and international terrorism, it can adapt to this threat as well. But doing so requires acknowledging that the next generation of radicalization is already here — and in many ways, it no longer resembles the world many investigators were trained to understand.
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