The dangers of categorism ...

... especially when it is faith-based: How the Media Botched the Arizona Shooting.

In their 1989 book How Do Journalists Think?, S. Holly Stocking and Paget H. Gross note that a typical reporter launches into a story with an investigative hypothesis, one that is often bolstered during the reporting process by “confirmation bias.” Only with great reluctance—in the face of overwhelming evidence to the contrary—is such a hypothesis normally discarded. Added to that is the weakness that competing hypotheses are tested one at a time, so that alternative explanations for the same data points are almost never considered simultaneously.

I rather doubt the shootings were as preventable as the author seems to think. Also, you could confiscate every legal firearm in the U.S. and there would be at least a quarter-billion others around. And it is easier to get a "piece" on the street than our sheltered chattering class apparently knows.