How much airport security is enough?

On a recent visit to a Perth court I had to pass through a metal detector several times because it kept sounding an alarm - oh Jeez, another of Beck's personal stories. My pockets had already been emptied of coins and keys so I couldn't figure out what was going on. In the end the security guard determined that the foil paper in a pack of cigarettes in my back pocket was triggering the walk-through detector. Sure it was a hassle being detained while a potential security threat relating only to the safety of others was sorted out, but that's life.

Lots of people are having a big sad about enhanced security measures in the wake of the failed underwear bomber's attempt to bring down an airliner - a threat to all passengers on board the aircraft. A notable complainer is former Customs Officer Allan Kessling, who reckons that airport screening is pretty much "window dressing/PR so beloved of politicians and loathed by the public":

Public safety in air travel must not be compromised by commercial considerations, such as increased costs due to slower movement of passengers, baggage or cargo. However it is delusional to imagine that safety or security will be provided by extended restrictions on the overwhelming majority of the public. While 100% security is impossible, much is done, quietly and unobtrusively, by Customs and other federal agencies, using known and well tested risk assessment techniques.

In the case of Umar Farouk Abdulmutallab, several recognized risk factors, not including his father warning the authorities or being on a danger list, were obvious before he came within cooee of Lagos airport. Any one of these warning bells would have been deafening to Australian Customs, using current procedures and systems. More than one would have woken the dead.

Kessling does not elaborate on the "risk factors" that would have made the underwear bomber an obvious threat but he does oppose "racial profiling". He also doesn't state what level of security screening is appropriate. So, let's take a quick look at how Israel's El Al screens passengers:

Passengers are asked to report three hours before departure. All El Al terminals around the world are closely monitored for security. There are plain-clothes agents and fully armed police or military personnel who patrol the premises for explosives, suspicious behavior, and other threats. Inside the terminal, passengers and their baggage are checked by a trained team. El Al security procedures require that all passengers be interviewed individually prior to boarding, allowing El Al staff to identify possible security threats. Passengers will be asked questions about where they are coming from, the reason for their trip, their job or occupation, and whether they have packed their bags themselves. The likelihood of potential terrorists remaining calm under such questioning is believed to be low (see microexpression). At the check-in counter the passengers' passports and tickets are closely examined. A ticket without a sticker from the security checkers will not be accepted. At passport control passengers' names are checked against information from the FBI, Canadian Security Intelligence Service (CSIS), Scotland Yard, Shin Bet, and Interpol databases. Luggage is screened and sometimes hand searched. In addition, bags are put through a decompression chamber simulating pressures during flight that could trigger explosives. El Al is the only airline in the world that passes all luggage through such a chamber. Even at overseas airports, El Al security agents conduct all luggage searches personally, even if they are supervised by government or private security firms.

Also, El Al is right into "profiling" and all flights are manned by plain-clothed armed security staff. Thus there has never been a successful terrorist attack on El Al.

Now whereas I agree that proposed rules that passengers not leave their seats during the last hour of a flight and have nothing on their laps are silly, I'm all for pre-boarding screening. But it does seem unlikely that a pat-down search is going to detect a small quantity of high-potency explosive hidden in a wearer's underwear. That seems to leave authorities with the choice of employing either full body searches or through-the-clothes scanning, both of which are regarded as overly intrusive.

El Al, being Israel's national carrier, does not have to operate at a profit. Commercial airlines do not have this luxury and must balance risks and costs. Mr Kessling seems to think that commercial airlines security is a superfluous farce and could be eliminated entirely. As someone who hasn't flown in over 20 years and has no plans of flying internationally anytime soon, I'm all for ripping out the metal detectors and other security devices and checks and relying exclusively on the experts who, according to Mr Kessling, are capable of intercepting a would be terrorist before he can get "within cooee" of an airport. Passengers will then be able to show up at the airport and get straight on that brand spanking new Airbus 380 without submitting to bothersome security formalities. Kaboom.