Aggressive assault, or “assault with intent to kill or for the purpose of inflicting severe bodily injury” (303), is increasing at “an astounding rate” (303) in the US. The rate is increasing despite the mass imprisonment of violent individuals, and the murder rate is increasing despite advances in medical technology. Without those two factors, rates of violent death would be worse. Grossman argues that the root cause of this propensity toward assault and murder is media violence. The same processes that have been used to condition soldiers to kill have been applied to the civilian population without the safeguards of the military.

Specifically, three major psychological processes facilitate violence: classical or Pavlovian conditioning, operant or Skinnerian conditioning, and observation and imitation of role models. Young people watch violent movies, with brutal killings and suffering, and associate them with entertainment, candy, dating, and pleasure. Additionally, they receive operant conditioning with rewards when they play video games that reward kills with targets downed and points. The role models in film are often lawless killers. To be sure, other factors, such as gangs, the loosening of family and religious ties, racism, and availability of weapons, are also responsible for the surge in violence.