Society has changed a lot in last century. With all the changes changes, there are several reasons why shootings are so prevalent in America now.
1) In the 1950’s, one parent could work while other stayed home and took care of the family. Now it is impossible for a family to survive on one income, so both parents have to work. With both parents working, kids have to take care of themselves after school without parent involvement.
2) Another big change is a “victim mentality” of kids growing up now. Anything goes wrong, it is not their fault, it is someone else. Big reason is the parents trying to make up for their absence, over protect their kids. This can be seen in a little league games when parents fight with referees and other parents. What ever happened with letting kids play a game without making a big deal out of it. Now kids see this and think the everything is a fight.
3) Violence acceptance in the society is another big reason. People and kids are exposed to killings, murders and other forms of violence on TV on daily basis. If you are exposed to something over and over, you will get desensitized and start believing that this is normal.
4) Violence in computer games is another big factor. Since most kids are home by themselves, because both parents have to work, they spend their time playing first-shooter games. Besides being exposed to violence on TV, violence in games further desensitizes kids and makes them believe that violence is a best was to solve their problems.
So when you combine Victim mentality in today’s youth and being desensitized to violence, you get a perfect storm for youth rage and thoughts of killing for any reason.