I find it difficult to believe that people will react that badly in a crisis.
I've ran relief NGOs overseas, relief for Katrina, two tsunami evacuations, military survival schools, and been in military operations in support of various crises ... I've seen people react that badly and worse in crises. Common sense is not so common anymore; like pab1 mentioned, its a mental preparedness issue. Current American culture is the least resilient.
Case in point, my 16yo son is taking EMT Certification B at the local community college. He is the youngest student in the class, he's a senior in HS and enlisting in the CG this summer. His first day of class was last friday, it's all day, 8 hours. These are people training to be first responders to someone else's crisis mind you ... half of them did not show up prepared for class (no book, study materials, pen, paper) and alot of them recently left military service and are using their GI Bill. Many of them did not pay attention. His "buddy" for infant CPR was a 20 something Navy wife, who freaked out because they ran out of training dummies. "OMG, there's not enough babies. What are we going to do? Um, excuse me, could someone go get us one of these infants? This is so stupid, you'd think they would've thought this through, y'know. I mean, OMG!" When I did the class there was one training infant, and a box of antimicrobial wipes so we could all share.
Psychologically its called the cycle of grief, and it applies to crisis. Our cultural has become mentally flabby when it comes to crises, which is why we have something called secondary PTSD, where the stress in someone else's life stresses us out to the point of depression ... imagine that. Something bad happens, and we go straight into a tailspin, riding the grief roller coaster and never getting off.
So I see it happening like this. (Mushroom cloud in the distance) OMG, what is that? Where's my phone, I need to get a video of this and post it on FB! Oh wait ... excuse me, sir? Is that bad? Should I do something? ... Where's the police? Shouldn't they be doing something about this? ... What am I going to do? Someone help ME! This can't be happening to me, I have important things to do today. This totally ruins my life. I'm a victim!
Its probably generational and regional, there are probably I higher percentage of the mentally prepared amongst the older rural folk. Definitely not among the younger metro folk.