The roots of violence

The massacres in Aurora, Colo., and at a Sikh temple near Milwaukee. The shootings outside the Empire State Building, in which an ex-employee killed his boss. Escalating gang warfare. In recent months, violence seemed to erupt everywhere. To get a better understanding of aggression of all kinds, we called on Stevan Hobfoll, a clinical psychologist and head of the behavioral sciences department at Rush University Medical Center.

By Bonnie Miller Rubin, Chicago Tribune reporter

September 12, 2012