A weekend of mass murder reflects how American violence goes viral

In El Paso, Dayton and Chicago, a weekend of horrific gun violence seemed on the surface to be another spasm of disconnected mayhem, people taking the lives of others almost at random. But on closer examination, the attacks served to illustrate how America’s lone-wolf shooters aren’t really alone.

Whether the proximate cause was political or personal, whether it grew out of ideological indoctrination, mental illness or some toxic blend of factors that left shooters isolated and damaged, each attack demonstrated a troubling disorder festering in modern America.

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