The spontaneous left-right blame in the Tuscon murders appears to overshadow a true blessing; Evil was apparently stopped by a prepared and armed citizen. For all the talk about this group or that group, the moral actions of a single individual are what matter. You must be prepared to immediately and individually act for the good of yourself and others!
Are you prepared to defend the innocent? Are you in a state of grace? If not, your first response will be to flee rather than to “risk” your soul. Do you personally every-day-carry basic emergency equipment? Yes, that could include a Beretta under your biretta! To be willfully ill-prepared is not good.
Save lives by being prepared.
As a reference, nutnfancy's "Close to Engage" video provides a nice commentary from last year.
Also consider the Sheepdog Concept video.