The book explains Berkowitz's Cognitive Neoassociation Model of Aggression.  It proposes that when people are repeatedly exposed to aggression they create in their minds more detailed and interconnected aggressive thought networks.  Exposure to aggression can trigger related feelings and can bring to mind knowledge of aggression-related skills, memories, and beliefs.

Chapter entitled "The Prometheus Engine" in part discusses military technology that is similar to video games.  With wars being waged from increasingly great distances, they're fought and seen through video game-type graphic systems.  Such technology turns killing into a "game".