This post is really just me recommending an article from a few years ago that has stayed with me. The article is from the Conservative news source, the National Review Online. I'm not recommending the site, but I do recommend the article Running Amok from 2012.
The article is about mass killings. It is not scientific or fact/stat based. It is a look at some of the history of mass killings, and how they have been looked at by various cultures. I like this article because it provides some context and depth for a seemingly insoluble problem. It doesn't suggest solutions or place blame. It is simply food for thought.