Good recommendations. But my take-away is that I am extremely unlikely to encounter an active shooter. Less than 12 incidents per year in a country of over 300 million people with an average of 3 deaths per incident. That means a one in 9,000,000 chance of my death by active shooter in the next year. Contrast with two to three thousand automobile deaths per month in 2010.
Those 36 deaths per year are just over 1/10 of the number of deaths from “Drowning and submersion while in or falling into bath-tub” (in 2000).
That same page of statistics shows 10,801 deaths due to “assault by firearm”. But even that is only a 1 in 331 chance in your entire lifetime.
Contrast with 787,000 deaths from heart disease in 2011. Diet and exercise should be vastly more important to all of us than assaults with guns.
Of course, those statistics aren’t uniform. You’re more likely to be assaulted in some places than others. If you live in one of those place, I recommend that you move, or if that doesn’t work for you, prepare to defend yourself, assuming the reason for those heightened assault statistics isn’t that your local government has made defending yourself difficult to do legally.