Prior to 9/11, most Americans found the idea that international terrorists could mount an attack on their homeland and kill thousands of innocent citizens not just unlikely, but inconceivable. Psychologically, Americans imagined that they lived in a security bubble. Terrorist attacks, including those on U.S. embassies in Tanzania and Kenya, occurred elsewhere. These beliefs were reinforced by the conventional wisdom among terrorism experts, who argued that terrorists sought not mass casualties but rather mass sympathy through limited attacks that called attention to their cause.
As we approach the fifth year without a second successful terrorist attack upon U.S. soil, a chorus of skeptics now suggests that 9/11 was a 100-year flood. They conveniently forget the deadly explosions in Bali, Madrid, London, and Mumbai, and dismiss scores of attacks planned against the United States and others that have been disrupted. The idea that terrorists are currently preparing even more deadly assaults seems as far-fetched to them as the possibility of terrorists crashing passenger jets into the World Trade Center did before that fateful Tuesday morning.
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[M]y best judgment is that based on current trends, a nuclear terrorist attack on the United States is more likely than not in the decade ahead. Developments in Iraq, Iran, and North Korea leave Americans more vulnerable to a nuclear 9/11 today than we were five years ago. Former Defense Secretary William Perry has said that he thinks that I underestimate the risk. In the judgment of most people in the national security community, including former Sen. Sam Nunn, the risk of a terrorist detonating a nuclear bomb on U.S. soil is higher today than was the risk of nuclear war at the most dangerous moments in the Cold War. Reviewing the evidence, Warren Buffett, the world's most successful investor and a legendary oddsmaker in pricing insurance policies for unlikely but catastrophic events like earthquakes, has concluded: "It's inevitable. I don't see any way that it won't happen."
Meanwhile, rather quietly, in places like Berkeley, people like Harold Palmer Smith, Jr. are "thinking the unthinkables":
I've asked my colleagues to think about the unthinkables, and they have done a very fine job. To be fair to the [Bush] administration, a lot of energy is being expended on making sure it doesn't happen. That's wise, but some effort has to go into thinking the unthinkable -- denying the denial. Universities particularly, broad-based universities like Berkeley, are the ideal place to carry on work like that. Furthermore, the Defense Department recognizes that and has sponsored this kind of work, and I think they're very pleased with their product.
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There's no indication whatsoever until there's a blinding flash of light, the proverbial mushroom cloud, and worse yet, if the device is exploded on the ground, then there's all the debris from the weapon and the activated soil, concrete, glass that's around it. It is a big, black plume, and it will move in whatever direction the wind is moving. Those people who are in suburban housing have to move, because exposure to that plume for short periods of time, many minutes to an hour, could be lethal. Those people have to move.
But if we go back now to the Houston experience, everybody is going to be scared to death, and everybody will want to move, in which case nobody can move, which is what Houston showed. That means then that those in the plume will suffer radiation death, and I don't mean cancer thirty years from now, I mean death that day. So, we've formulated a problem which we call selective evacuation, and your guest a few days ago, Professor Smelser, has been a great leader in this. But it's quite simple. Those who will be in the plume should move, and those that would not be in the plume should seek shelter -- the deeper, the better. Unfortunately duct tape would be a good idea, to seal windows and things like that. One has to shelter oneself for periods of many hours, not many days.
So, it is not the Armageddon that we think of, or the nuclear exchange in the Cold War. This is one single nuclear weapon which will have death and devastation but only for perhaps a mile around the weapon, and then we fear this plume, and there, if we do it right and move the people who are in it and keep the other people sheltered, the number of fatalities goes way, way, way down. It's a very humanitarian undertaking, but it's fraught with the technology problems of how do you predict which way it's going to go, and more importantly, the psychological problems: how do you convince people to stay put with a nuclear explosion going off, or maybe equally difficult, how do you make people move, particularly since you may not have the communications system that you would like to have?
There are legal aspects here. There are political science aspects: who's in charge? There are organizational questions. The interdisciplinary nature of Berkeley and its surrounding national laboratories [makes it] ideal for us to look at [the problem]. Furthermore, [it's] better to have a university look at this terrible problem than for the government to do it, because the government then will be telling the people they honestly fear it's going to happen. There is, as we call it, plausible denial when a university and its academic thinkers take it on, but we're undertaking this project for the very reasons that you and I have been discussing.
What I'm interested in is who, if anybody, is really thinking through the chain of events in world politics likely to unfold in the days and weeks and months and years that will follow, if Graham Allison's fears flash blindingly true. (And I mean thinking them through seriously and responsibly, not that Three Conjectures nonsense.)
