A Hispanic man accused of killing eight people at an outlet mall in Texas last month held a mix of views consistent with neo-Nazism and involuntary celibate extremism The mass shooting appears among recent cases that highlight a "persistent and lethal threat" to U.S. security posed by "lone offenders and small groups motivated by a range of ideological beliefs and personal grievances," the Department of Homeland Security said. FBI director Christopher Wray calls it "salad bar" extremism. In the U.K., it's known by MUU -- mixed, unstable or unclear. Security firm Valens Global calls it "composite violent extremism." The terms refer to "idiosyncratic patterns of radicalization," says Valense Global's Daveed Gartenstein-Ross, who leads a project on domestic extremism for the Foundation for Defense of Democracies. "Traditionally, terrorism is thought of as being largely nested within a single ideology," Gartenstein-Ross told ABC News. "What we're seeing is violent extremists who display an amalgamation of different disparate beliefs, interests and grievances."
Examples include Frank James, who pleaded guilty to federal terrorism charges for a 2022 shooting in the New York City subway; Nikolas Cruz, who was sentenced to life in prison for the 2018 mass shooting at Florida's Marjory Stoneman Douglas High School; and Zale Thompson, who was shot and killed by NYC police officers after attacking them with an ax in 2014. John Cohen, a former U.S. Department of Homeland Security official, points to several factors contributing to this phenomenon in the U.S., including a highly-polarized society in which some people feel that violence is acceptable, and an online and media environment that is "saturated" with extremist content. "You spend time online, you not only can find the justification for the conduct of that attack, but you can find content that will provide you detailed instructions on how to do it," Cohen said.
Gartenstein-Ross said, "We as a people are becoming more incoherent," he said. "Extremists are becoming more incoherent as well." Composite violent extremism poses several challenges to law enforcement, Gartenstein-Ross noted, from determining when someone who is ideologically idiosyncratic becomes a threat to how to intervene, to how to define their community.