One important fact that the media fail to mention: the school shooters are not adults with guns, they are school students. Why? Three things to think about:
These students have not heard the Bible mentioned, or seen one, in their schools.
Many of these students have only one parent in the home.
Many of these students are prescribed psychoactive drugs, or are using illegal drugs.
Parents are aware that children are emotional, erratic, and ill-informed, and hope to remedy that in 18 years. The educational system does not work as well as it used to, and rather than changing those characteristics, it is content to make good socialists of them.
Most adults still believe in God; that's how we are able to own guns and not be killers. As we die off, things are not likely to get better.