Preppers often think of all the bad things that could, and do, go wrong.
From natural disasters like earthquakes, tornadoes, and hurricanes (to name a few) to man-made calamities like earthquakes from fracking and terrorist events, we dwell on bad stuff.
And while terrorist events take center stage, much more harm is done to mankind by Mother Nature. THAT is what we need to be concerned with, primarily.
At the end of the day, you must be prepared for anything.
The recent earthquakes left many deeply shaken. A friend was in an elevator inside a high-rise; another watched from the street, stupefied, as a nearby condominium swung side to side on its foundations.