This is a terrible thing and I don't know what the answer is to fix it. I begin with the home. Kids are not being disciplined anymore and they have no consequences for their actions. Parents put kids in front of video games and tv or drugging them because they can't take their energy instead of being a parent and spending time with your kids, teaching them right from wrong, going to church, displaying the value of life to them, etc. How many of them come from broken families with only one parent and no guidance?
Kids need consequences for their actions, not a hug and told that is ok, just don't do it again. An example - my wife is a 4th grade teacher. Last year a kid told her that he was going to f*****g murder her. She sent him to the principal and he didn't understand why the kid wasn't allowed back in her room that day. He and the social worker told her not to contact the police. ARE YOU KIDDING ME!!! A 9-10 year old kid knows right from wrong and exactly what came out of his mouth. I was and still am livid, especially when things like this happen again. There is a good chance that kid who told my wife that could be the next one to do it. She went against her boss and filed a police report, but was told by police he was too young to press charges. AGAIN, WTF!!!
We need to get back to teaching kids respect, the value of life, the value of a family, and having consequences. Once God left our schools, it started leaving our homes and I believe that has had a big impact on our country. There is no easy fix for this. Blaming the gun is the easy thing to do, rather than look at the root cause and admit we have gone awry from our values in this country. We have systems in place to keep people who shouldn't have guns from actually acquiring them, but our government entities don't talk to each other to share the valuable information we have.
I don't have all the answers, but I do know that my guns haven't walked out of my house and killed anyone yet. So I know they are not capable of doing it without someone crazy enough to actually pull the trigger. Sorry for my rant.