What this reminds me of is that basically in aviation security, you are trying to balance three factors, and it's very difficult to balance them all correctly. You're trying to actually provide a screen that will prevent people who are intent to doing harm to airplanes to get on an airplane. You're trying to provide the appearance of security, both because passengers find it reassuring and also because it may deter terrorists a bit, if they visibly see a lot of security activity going on. But you're also trying to preserve the utility of air transportation. Obviously if you fully interrogated, stripped, ran a detector over every piece and every person that got on an airplane, you would dramatically reduce the risk of flying but air transportation would become unusable.Damn. Let's all get nekkid.
We do not yet have very consistent procedures, airport-to-airport around the world. And people who will get stopped at one airport don't get stopped at another or who would be stopped by one person don't get stopped by another. That's a big problem. The second thing is that we need a way, I think, to separate the passengers who don't present much of a threat to passengers who are more likely to present a threat.