And people saw New Orleans after Katrina, and Boston after the marathon bombing. They didn't yell. They just went out and bought their first gun. Or they bought a camera or smartphone live-streaming app and started randomly recording police encounters.
So now "prepping" by such means as stockpiling food and ammunition is a normal part of society. This, despite blog and television portrayals of such people as wingnuts. People are quietly preparing for surviving a civil war, under the guise of disaster preparedness.
Once the watershed event occurs, whatever it may be, it will not be pretty. If even 0.1% of the population are just waiting for the camel's back to break before firing one shot, that's still a lot of bullets in the air.