More Nuclear Terrorism

Mike Levi and Graham Allison are having a little throwdown over “How Likely is a Nuclear Terrorist Attack on the United States?” on the CFR website.

Oddly, both agree that the stated topic of discussion—the probability of an attack—is irrelevant:

• Levi: “How likely is a nuclear terrorist attack on the United States? I doubt anyone knows. I also suspect that the exact answer isn’t all that important—even a small chance of catastrophe is worth worrying about.”

• Allison: “Rather than quibble over percentage points, the bottom line is recognition that risk equals probability times consequences. Even skeptics who believe that experts overestimate the probability find it difficult to discount the risk.”

Right, so what are we arguing about, again?

It seems to me that probabilistic models are only useful to identify the optimal allocation of resources in deterring, preventing and responding to nuclear terrorist attacks. As Matt Bunn said in the comments on an earlier post:

… a systematic approach helps in focusing the discussion, identifying areas of disagreement, identifying areas where additional information would reduce the range of uncertainty, and, yes, offering an at least somewhat more focused approach to assessing which policy options might be most important.

I appreciate Mike’s effort to point out that the risk of failure might deter terrorist groups from investing seriously in nuclear weapons, but I wish this debate were about a particular policy that might be controversial—say, domestic nuclear detection efforts that some jerk called an “appeal to the instincts of defense thinkers who want to act boldly in the world but are also, at heart, isolationists.”

Just a thought.