“This attack is a response to the Hispanic invasion of Texas,” begins the manifesto of the El Paso shooter, who killed twenty-two people and injured twenty-four others at a Walmart on August 3, 2019. The gunman argued that he had been forced to commit this mass murder, writing: “I am simply defending my country from cultural and ethnic replacement brought on by an invasion.”

Eight years earlier, a far-right militant in Norway committed a strikingly similar act of terror; in July 2011 he killed seventy-seven people with a homemade car bomb and mass shooting at a youth camp. He denounced supposed “demographic warfare,” claiming that “Islam is growing rapidly in Western Europe; from 50,000 in 1955 to 25 million today.” He termed this deliberate plot to replace white Europeans with black and brown migrants until Europe has no white population left.

In the past decade, countless mass killers around the world have claimed motivated by a belief in the imminent genocide of white people. Though they have much in common (all white, all men, predominantly radicalized online) they also come from four different continents, span a breadth of ages, and articulate a vast array of political beliefs.