Citizens are not prepared for attacks because there is a bias against the public by nearly every expert and government official. In emergency preparedness, there is this belief that public will panic, that the public is not to be trusted, that there will be looting.

We gauge risk literally hundreds of times per day, usually well and often subconsciously. We start assessing risk before the disaster even happens. We are doing is right now. We decide where to live and what kind of insurance to buy, just like we process all kinds of everyday risks: we wear bike helmets, or not. We buckle our seatbelts, smoke cigarettes, and let our kids stay out until midnight. Or not.

The one thread that was most surprising and most consistent was the lack of fear that people felt at the worst moment. They felt a lot of fear in early stages, when they're just realizing what's happening. But then things really seemed to be at their peak of terror, the fear went away. You can imagine why that's useful. At that moment your brain needs to focus all its attention on surviving, so people will feel a sense of calm as their brain tries to sort out a plan.

Well, there isn't any one profile of a survivor, but there are profiles. Depending on the disaster you have certain advantages and disadvantages just based on who you are. Women are more likely to survive hurricanes. In hurricanes the deaths come from floods and people driving through high water. That's much more likely to be a man who dies that way.

By sort of combining the research of a lot of smart people, I came up with an equation for dread [dread=uncontrollability+unfamiliarity+imaginability+suffering+scale of destruction+unfairness]. The dread equation is a simplification, but it's a way to explain why we fear something so much when it is so unlikely. Part of it is the lack of control. That's why we're more scared of plane crashes than car crashes even though we know rationally which is more dangerous.

A lot of the time you see a warning, in the subway, or in a movie theater, the main thrust of the warning will be to not panic if there is an emergency. To listen to directions. Now that's a waste. They could have given you information, but you can see their expectation that you're going to screw up.

The evil genius of terrorism is that that maximizes unfamiliarity, imaginability, suffering, scale of destruction, unfairness. It's really important to understand why terrorism is so frightening because it is a psychological war and until you understand it and try to reduce the dread, until then you become like a force multiplier for the terrorists inadvertently because you'll tend to overreact to terrorist attacks because the dread factor is so high.