I’m in an ongoing discussion with a friend about why there hasn’t been another terrorist attack in U.S. territory since September 11th. I had tried to do some google research, but found that politics, particularly politics surrounding the Presidential election, made it really difficult to find any clear non-partisan assessments. Bush supporters pounded the war drums and Kerry supporters claimed the threat was over-hyped.

My friend and I had several theories. One was that the threat from terrorism is overstated, and that terrorists are less powerful, interested, organized and numerous than reported. There’s some support for this in the 9/11 Commission Report:

Al Qaeda and its affiliates are popularly described as being all over the world, adaptable, resilient, needing little higher-level organization, and capable of anything. The American people are thus given the picture of an omnipotent, unslayable hydra of destruction. This image lowers expectations for government effectiveness.

It should not lower them too far. Our report shows a determined and capable group of plotters. Yet the group was fragile, dependent on a few key personalities, and occasionally left vulnerable by the marginal, unstable people often attracted to such causes. The enemy made mistakes-like Khalid al Mihdhar’s unauthorized departure from the United States that required him to enter the country again in July 2001, or the selection of Zacarias Moussaoui as a participant and Ramzi Binalshibh’s transfer of money to him. The U.S. government was not able to capitalize on those mistakes in time to prevent 9/11.

Yet, we also think that terrorism is pretty easy to do, if you’ve got people who are willing to die, and if you just want to sow the seeds of fear, rather than do something spectacular every single time. Individuals could simply blow themselves up in the unsecured parts of airports, public transportation, shopping malls, cafes, and people would be afraid even if few innocents died. With the bombings in Madrid and London, the terrorists have shown that they are capable of even more than this.

John Arquilla of the Naval Postgraduate School, someone I really respect a lot, offered this view in yesterday’s Chronicle.

What do Shout readers think?