If parents do not teach their children proper behavior, nobody will. The
school’s job is to teach facts and how to use them. Few children go to
church, and those who go pay little attention to the sermons. The job of
raising good citizens falls to the parents. As adults, uncivilized people will
have trouble finding good jobs, interesting friends and pleasant spouses.
They will embarrass their parents and be unable to support them in old
age. The parents will have no one but themselves to blame.
The government can provide guidelines for media censorship like movie and videogame ratings. However, it is ultimately the responsibility of parents to censor the media to their children. If someone wants to play "Grand Theft Auto" with their five-year-old, that's up to the parent. It is not up to the government to tell parents how to raise children.