The Comparative Risk of Terrorism

Good essay from the Wall Street Journal:

It might be unrealistic to expect the average citizen to have a nuanced grasp of statistically based risk analysis, but there is nothing nuanced about two basic facts: (1) America is a country of 310 million people, in which thousands of horrible things happen every single day; and (2) The chances that one of those horrible things will be that you’re subjected to a terrorist attack can, for all practical purposes, be calculated as zero. Consider that on this very day about 6,700 Americans will die…. Consider then that around 1,900 of the Americans who die today will be less than 65, and that indeed about 140 will be children. Approximately 50 Americans will be murdered today, including several women killed by their husbands or boyfriends, and several children who will die from abuse and neglect. Around 85 of us will commit suicide, and another 120 will die in traffic accidents. […] Indeed, if one does not utter the magic word “terrorism,” the notion that it is actually in the best interests of the country for the government to do everything possible to keep its citizens safe becomes self-evident nonsense. Consider again some of the things that will kill 6,700 Americans today. The country’s homicide rate is approximately six times higher than that of most other developed nations; we have 15,000 more murders per year than we would if the rate were comparable to that of otherwise similar countries. Americans own around 200 million firearms, which is to say there are nearly as many privately owned guns as there are adults in the country. In addition, there are about 200,000 convicted murderers walking free in America today (there have been more than 600,000 murders in America over the past 30 years, and the average time served for the crime is about 12 years). Given these statistics, there is little doubt that banning private gun ownership and making life without parole mandatory for anyone convicted of murder would reduce the homicide rate in America significantly. It would almost surely make a major dent in the suicide rate as well: Half of the nation’s 31,000 suicides involve a handgun. How many people would support taking both these steps, which together would save exponentially more lives than even a — obviously hypothetical — perfect terrorist-prevention system? Fortunately, very few. (Although I admit a depressingly large number might support automatic life without parole.) Or consider traffic accidents. All sorts of measures could be taken to reduce the current rate of automotive carnage from 120 fatalities a day — from lowering speed limits, to requiring mechanisms that make it impossible to start a car while drunk, to even more restrictive measures. Some of these measures may well be worth taking. But the point is that at present we seem to consider 43,000 traffic deaths per year an acceptable cost to pay for driving big fast cars.

Kevin Drum takes issue with the analysis:

Two things. First, this line of argument — that terrorism is statistically harmless compared to lots of other activities — will never work. For better or worse, it just won’t. So we should knock it off. Second, even in the realm of pure logic it really doesn’t hold water. The fundamental fear of terrorism is that it’s not just random or unintentional, like car accidents or (for most of us) the threat of homicide. It’s carried out by people with a purpose. The panic caused by the underwear bomber wasn’t so much over the prospect of a planeload of casualties, it was over the reminder that al-Qaeda is still out there and still eager to expand its reach and kill thousands if we ever decide to let our guard down a little bit. So even if you agree with Campos, as I do, that overreaction to al-Qaeda’s efforts is dumb and counterproductive, it’s perfectly reasonable to be more afraid of a highly motivated group with malign ideology and murderous intent than of things like traffic accidents or hurricanes. Suggesting otherwise, in some kind of hyperlogical a-death-is-a-death sense, strikes most people as naive and clueless. It’s an argument that probably hurts the cause of common sense more than it helps.

While I agree that arguing that terrorism is statistically harmless isn’t going to win any converts, I still think it’s an important point to make. We routinely overestimate rare risks and underestimate common risks, and the more we recognize that cognitive bias, the better chance we have for overcoming it.

And Kevin illustrates another cognitive bias: we fear risks deliberately perpetrated by other people more than we do risks that occur by accident. And while we fear the unknown — the “reminder that al-Qaeda is still out there and still eager to expand its reach and kill thousands if we ever decide to let our guard down a little bit” — more than the familiar, the reality is that automobiles will kill over 3,000 people this month, next month, and every month from now until the foreseeable future, irrespective of whether we let our guard down or not. There simply isn’t any reasonable scenario by which terrorism even approaches that death toll.

Yes, the risks are different. Your personal chance of dying in a car accident depends on where you live, how much you drive, whether or not you drink and drive, and so on. But your personal chance of dying in a terrorist attack also depends on these sorts of things: where you live, how often you fly, what you do for a living, and so on. (There’s also a control bias at work: we underestimate the risk in situations where we’re in control, or think we’re in control — like driving — and overestimate the risks in situations where we’re not in control.) But as a nation we get to set our priorities, and decide how to spend our money. No one is suggesting we ignore the risks of terrorism — and making people feel safe is a good thing to do — but it makes no sense to focus so much effort and money on it when there are far worse risks to Americans.

Jeffrey Rosen wrote about this last year. And similar sentiments from Baroness Murphy of the British House of Lords.

Remember, the terrorists want us to be terrorized, and they’ve chosen this tactic precisely because we have all these cognitive biases that magnify their actions. We can fight back by refusing to be terroroized.

Posted on January 12, 2010 at 6:15 AM • 88 Comments