Wednesday, September 20, 2006

A Skewed Perspective on Terrorism

When economists think about terrorism their thinking tends to be muddled. Glen Whitman, an associate professor of economics and co-proprietor of Agoraphilia, amply demonstrates muddleheadedness in "Perspective on Terrorism," where he says this:

At Cato Unbound, in response to a lead essay by John Mueller, Clark Kent Ervin rejects the comparison of the death rate from terrorism to the death rates from bee stings, lightning, drowning, etc. Ervin’s argument is so unpersuasive (to me) that I think it deserves a fisking.

It is undoubtedly true that Americans are far more likely to die from “bee stings, lightning, or accident-causing deer” than terrorism, but so what? ... This statistical argument implicitly equates deaths from bee stings, lightning or close encounters with marauding deer with deaths from terrorism.

They should be equated. It doesn’t make sense to spend a billion dollars to prevent one death by terrorism if the same billion dollars could prevent ten or a hundred deaths by other causes. Death is death. It can be sensible to give different treatment to deaths by different causes, but only if there’s some reason to think one cause of death is more easily deterred than another.

Ervin may have made his case badly, but he is right and Whitman is wrong. To see why, let's go back to Mueller's statement

Although polls continue to show Americans notably concerned that they or members of their families might die at the hands of terrorists, astronomer Alan Harris has calculated that, at present rates and including the disaster of 9/11 in the consideration, the chances any individual resident of the globe will be killed by an international terrorist over the course of an 80-year lifetime is about 1 in 80,000, about the same likelihood of being killed over the same interval from the impact on the Earth of an especially ill-directed asteroid or comet. At present, Americans are vastly more likely to die from bee stings, lightning, or accident-causing deer than by terrorism within the country. That seems pretty safe.

That seems "pretty safe" only because the United States (and many other countries) have taken affirmative steps to detect and thwart terrorist attacks before they occur. We have seen the enemy's successes. But we are unaware of many of his failures because it is stupid to give the enemy an inkling of how we have achieved all of our successes.

Comparing the ex post death rate from terrorism with such unpreventable and/or random events as asteroid strikes, bee stings, lightning strikes, or deer-caused accidents is a classic demonstration of academic cluelessness. Those unpreventable and/or random events will occur regardless of terrorism. Terrorism is an additional threat -- not an alternative one. The worst mistake we can make is to underestimate that threat.

Now, Whitman would say that we can spend less money on the war on terror and more to prevent asteroid strikes, for example, and that we ought to determine the right balance of spending between the two activities. That's fine, as far as it goes, but a correct determination of the balance of spending cannot be made by using probabilities of the type cited by Mueller.

Asteroids, bees, lightning, and deer -- unlike terrorists -- are not sentient enemies. Ignoring those "threats" will not enable them to increase their "attacks" on us; they will do what they will do, according to the "laws of nature." Ignoring terrorists, on the other hand, certainly would enable them -- and encourage them -- to increase their attacks on us. The apparently low probability of being killed by a terrorist is low precisely because we have spent a lot of money to make it low.

Moreover, we must continue to spend a lot of money to keep that probability low. If we fail to do so, we will then find out what it is like to be besieged -- to live lives that are markedly poorer, filled with anxiety, and isolated from that large part of the world in which Islamism will have triumphed.

Is it possible to eliminate that prospect and avoid a future of perpetual terrorism? I believe that it is, if we put enough money and effort into the war on terror. And if we never relent, even after terrorism is reduced to a "law enforcement" problem. Evil always lurks.

Because civilization depends on continually making the effort, of never giving in. It needs to be cared for by men of goodwill, protected from the dark. These people [the Romans] gave in. They stopped caring. And because they did, this land fell under the darkness of a barbarism which lasted for hundreds of years.

-- From Cicero's "The Dream of Scipio" (Thanks to Verity of Southern Appeal.)