When news broke April 16 of the worst mass shooting in U.S. history, the question many horrified Americans most wanted to answer was, "Who was the shooter?" It's an urgent and understandable question, but one that rests on a dangerous assumption: that if everyone only knew more about the killer, then what he did would make sense--and…

Aggression and violence in the United States remain vexing problems that require several key responses. First, universal prevention programs and targeted treatment strategies for people at risk of aggressive behavior are needed to address the established link between mental illness and the potential for violence. Sadly, many perpetrators of gun…