But you can help it. What is your payoff matrix? How much effort do you think it's worth to prepare for every possible eventuality? You'll notice that while fl

But you can help it. What is your payoff matrix? How much effort do you think it's worth to prepare for every possible eventuality? You'll notice that while flight crew give instructions on how to use various safety equipment, they don't actually run through drills where the masks comes down and they check to make sure they are put on correctly; they don't run through drills where the passengers actually leave the aircraft; they don't do all that while dumping simulated smoke in the cabins. You'll notice that while there are tests of the evacuation alarms around, say, a nuclear power plant, they don't actually run mass tests to see if everyone can evacuate in time. New York City is in the 50-mile evacuation zone for Indian Point Energy Center. And those "plans" are more like "fantasy". What you can do is read about disaster planning for those different scenario (hurricane, tsunami, nuclear reactor meltdown, bomb shelters, plastic sheeting & duct tape against biological attacks, fire drills, airplane evacuations, etc.), see what the plans are, and figure out why people came to the conclusions that they did. There's no reason to make wild guesses about what you think it should be when there's plenty of material for you to ground your thinking. Regarding specifically nuclear bomb shelters, read Freeman Dyson's essay at http://scilib.narod.ru/Physics/Dyson/Weapons_and_Hope/Weapons_Hope.htm#chap08 http://scilib.narod.ru/Physics/Dyson/Weapons_and_Hope/Weapon... . For the US, a nuclear shelter program could destabilize the arms race, since we would be planning to defend ourselves against Soviet attacks, giving the Soviets cause to think that we would attack them knowing that we would be more likely to survive. The Swiss bomb shelters don't destablize international politics in anything like the same way.