The San Diego suspects were 10 and 12 at the time of the mosque shooting in Christchurch. They grew up consuming that content. PERIL's Cynthia Miller-Idriss in NBC News on the online ecosystems turning radicalization into a template. bit.ly/4vbzFRC
A 75-page document and a livestreamed video apparently created by the gunmen echo previous shootings fueled by extremist ideology.
