Do CGI Guns Lead to Real Guns?

Violent video games have always been accused of 'desensitizing' players to violence and causing an increase in aggression for those who play them according to several studies. It is because of these studies that mass murders such as the Sandy Hook shooting are blamed on violent video games. This accusation is too severe, as video games can increase aggression but don't necessarily cause violent crime. One example of such a study was done in France in March. This study showed that individuals who play violent video games for three days and are then subjected to computer game and asked to finish a story are more violent and hostile as opposed to individuals who play non-violent video games. The computer game allowed players to punish fake opponents with a variety of loud noises, controlling their volume and duration. The violent video game players were deemed more aggressive than the non-violent video game players because "after reading the beginning of the stories, they were more likely to think that the characters would react with aggression or violence... also gave their opponents louder and louder headphone blasts after each day of game play," indicating an increase in hostile behavior or expectations due to exposure to violent video games.
This study is reasonable, the games were either extremely violent or dangerous but not graphic and there was a clear difference between the violent gamers and the peaceful games, as well as a notable increase in the violent gamers' hostility. So video games causing an increase in aggression is a logical theory.
However, this does not mean that video games cause mass murder. Call of Duty 4, the same video game included in the aforementioned study has sold an impressive 10 million units and counting, but there aren't 10 million mass murderers due to Call of Duty 4. Dr. Laura Davies, a child and adolescent psychiatrist believes that violent video games are a danger to the moral codes of children, but she still agrees that there are children who are "unable to so easily differentiate between fantasy and the real world. They might not fully understand that the people they harm have real lives and real families" and have their intensity magnified by violence in video games. While most children mature and are able to differentiate fantasy and reality when they are old enough to carry out such crimes, some individuals may never mature. And for these people, violent video games are dangerous and may contribute to an act of violence. But could violent video games be the sole cause for a mass murder? I don't think so.
What do YOU think, nonexistent reader? Do you agree with this post or do you think I'm lazy and should've made more blog posts over the quarter and genuinely tried to make them better?