Violent video games are well known to increase aggressive behavior and aggressive thoughts and to decrease empathy and a desire to help others. These video games, along with relentless violence on television, also desensitize the young mind to pain and suffering.
Given that the US Army uses video games and gaming systems to prepare soldiers for combat, it is clear that such games are effective assault simulators.
These games alone do not create civilian killers, but they undoubtedly help train disturbed youths to carry out brazen and devastating attacks and are therefore a significant threat to our society.