Do you think violent computer games have a subliminal effect on their users?

if you go back through the past 100 yrs of this country,you will see a rise in violence,with the rise of the video games with the killing area,theirs been more high speed racing accidents with teens,and school shootings with teens,you could also blame rap music for its such violence betrayal of good life,seems if you kill someone and get away,you get a street badge like to boyscout,and its cool,America better do something because it WILL only get worse,imagine in 15 yrs?