It seems to me that the complaints about the failure to stop the most recent terrorist attempt on Christmas are valid. Valid in the sense that a sufficient warning had been provided to the US government to trigger at least a careful search of the terrorist prior to allowing him to board a plane.
On the other hand, I think that there is no way to stop all would-be terrorist, aside from requiring passengers to travel nude following full-body cat scans. Anytime you bring people together in a closed space there is a risk of criminal behavior. Nate Silver has provided a calculation of the true risk of being a victim of airborne terror:
Over the past decade, according to BTS, there have been 99,320,309 commercial airline departures that either originated or landed within the United States. Dividing by six, we get one terrorist incident per 16,553,385 departures.
These departures flew a collective 69,415,786,000 miles. That means there has been one terrorist incident per 11,569,297,667 mles flown. This distance is equivalent to 1,459,664 trips around the diameter of the Earth, 24,218 round trips to the Moon, or two round trips to Neptune.
Assuming an average airborne speed of 425 miles per hour, these airplanes were aloft for a total of 163,331,261 hours. Therefore, there has been one terrorist incident per 27,221,877 hours airborne. This can also be expressed as one incident per 1,134,245 days airborne, or one incident per 3,105 years airborne.
Am I wrong to ask how many more billions of dollars we are willing to spend to reduce this extremely small risk? Are we getting our money’s worth from the huge amounts spent on the TSA? Certainly there are a great number of risks that are far larger than this that could use the funding for risk mitigation.
Update: And today, Holman Jenkins, Jr., writes an opinion piece in the Wall Street Journal noting that airport security is actually very good.
Silly are the outrage and accusations simply because Mr. Abdulmutallab was on a list (along with 550,000 others about whom suspicions have been raised) without keeping him off a flight. Critics really seem to be saying that, politically, security personnel can’t maintain any lists that are bigger or different from the no-fly list—which is ridiculous.
Let’s be realistic—efficient counterterrorism requires the setting of priorities. There has to be more than one list. Yet the reaction to Farouk Abdulmutallab may soon mean there will be one list and eventually everybody will be on it and nobody will be able to fly.