In America, unthinkable violence has become routine.  In the wake of the Buffalo and Uvalde mass shootings, David Remnick speaks with the researchers Jillian Peterson and James Densley, whose book “The Violence Project” is the most in-depth study of mass shooters. Pro-gun politicians may continue to block any measures to reduce violence, but we can understand better a different side of the equation: what motivates these crimes. David Remnick speaks with two criminal-justice researchers who have studied mass killers, James Densley, of Metropolitan State University, and Jillian Peterson, of Hamline University. They point out that mass shootings have risen alongside deaths of despair, including overdoses and suicide.  “The perpetrator goes in with no escape plan,” Peterson points out.  “What we can learn from suicide prevention can teach us how to prevent some of these mass shootings.  We haven’t connected these two things.”  Remnick is also joined by Keeanga-Yamahtta Taylor, who wrote about the Buffalo attack for The New Yorker; and we hear from a 70-year-old resident of Uvalde, Texas, about the aftermath of the killings in a tight-knit community.