A new paper on trusted traveler programs from RAND Corp goes into some detailed math analysis of various approaches to a trusted traveler program. In such a program, you pre-screen some people, and those who pass go into a trusted line where they receive a lesser security check. The resources saved in the lesser check are applied to give all other passengers a better security check. This was the eventual goal of the failed CLEAR card -- though while it operated it just got you to the front of the line, it didn't reduce your security check.

The analysis shows that with a "spherical horse" there are situations where the TT program could reduce the number of terrorists making it through security with some weapon, though it concludes the benefit is often minor, and sometimes negative. I say spherical horse because they have to idealize the security checks in their model, just declaring that an approach has an X% chance of catching a weapon, and that this chance increases when you spend more money and decreases when you spend less, though it has diminishing returns since you can't get better than 100% no matter what you spend.

The authors know this assumption is risky. Turns out there is a form of security check which does match this model, which is random intense checking. There the percentage of weapons caught is pretty closely tied with the frequency of the random check. The TTs would just get a lower probability of random check. However, very few people seem to be proposing this model. The real approaches you see involve things like the TTs not having to take their shoes off, or somehow bypassing or reducing one of the specific elements of the security process compared to the public. I believe these approaches negate the positive results in the Rand study.

This is important because while the paper puts a focus on whether TT programs can get better security for the same dollar, the reality is I think a big motive for the TT approach is not more security, but placation of the wealthy and the frequent flyer. We all hate security and the TSA, and the airlines want to give better service and even the TSA wants to be hated a bit less. When a grandmother or 10 year old girl gets a security pat down, it is politically bad, even though it is the right security procedure. Letting important passengers get a less intrusive search has value to the airlines and the powerful, and not doing intrusive searches that seem stupid to the public has political value to the TSA as well.

We already have such a program, and it's not just the bypass of the nudatrons (X ray scanners) that has been won by members of congress and airline pilots. It's called private air travel. People with their own planes can board without security at all for them or their guests. They could fly their planes into buildings if they wished, though most are not as big as the airliners from 9/11. Fortunately, the chance that the captains of industry who fly these planes would do this is tiny, so they fly without the TSA. The bypass for pilots seems to make a lot of sense at first blush -- why search a pilot for a weapon she might use to take control of the plane? The reality is that giving a pass to the pilots means the bad guy's problem changes from getting a weapon through the X-ray to creating fake pilot ID. It seems the latter might actually be easier than the former.

Overall, it's hard to imagine a TT program that I wouldn't want if I were a terrorist. Anything that creates an easier path through security is a potential hole. With no consequences for trying, I can put all my recruits through the screening process to see if I can get some through, or I can try to make use of people who have passed the pre-screening, by hiding things in their bags or shoes, or even kidnapping their children and making them do my bidding. The big question is how the reduced security at the TT line works. If it's a reduced rate of random screening, it's not worth it for me. If it's a removal of a step, such as "no scan of the shoes" then I will know that and just put weapons in the shoes of people sent through the TT line, giving them a very high probability of success. (This assumes the shoe screening approach of the TSA is really a good idea; let's assume that for the moment.) This math is not in the Rand analysis. You could even break into the house of a regular air commuter who is a TT and replace their shoes, then place somebody (who boarded unarmed in the higher-security line) in the seat next to them.

Earlier I wrote that since the terrorists want terror, and use violence as a means to terror, the TSA may feel their role is not to stop the attacks, but to stop the fear, which is the real weapon, and because of this they engage in things that appear to keep the public safe even if they don't really do that. TT programs may fit with this model, both in appearing to increase safety slightly, but most importantly in reducing the burden security places on influential people and good airline customers. The TSA knows it is pushing the limits of public acceptance. TT programs may allow it to do more extreme security on the general public than it could otherwise get away with -- not in financial cost, but in political cost.

This presents a different way of thinking on the TSA mindset. They may feel that in order to do the job of preventing attacks, they need to employ more unpleasant security approaches than the public would accept. The way to get the public to accept them is to not apply them to the important, rich or revenue generating members of the public, as well as to those that make the system look bad, like kids and grandmothers. The intensive security can then be applied to the rest of the public. This gives the appearance of extreme security even if terrorists are able to exploit the TT line and its lower security. If you add some random checks with the intense security to the TT line, rather than making it a 100% pass on them, you might actually provide overall superior real security.

It's also possible that this could be viewed, even in a rational analysis, as deliberately reducing the overall security of the system a small amount while reducing complaints and opposition to the system a larger amount.

Naturally, if the approach of "placate the powerful and strip-search the masses" were expressed as official policy, it would never fly. (Do you want to fly today?) It is indeed, rather unfair and far from egalitarian. And of course, they seem unable to admit that one can have too much security, and one might indeed reduce the actual security in order to reduce the hassles of it, though many of the public might be fine with that. In addition, the reality is that those in the public who can get into the TT program will embrace it. It saves them hassle, and makes them feel superior to boot. Only a minority seem to object to the concept of a background check. After years of TSA rule, the normally repugnant idea that you should need a background check to travel with convenience in your own country has grown more acceptable, just as the idea that being told your choice is to be photographed nude or groped has become acceptable.

What's the path to real security? Strong cockpit doors, bomb-proof luggage containers and aircraft designs that can withstand a small explosion from a carry-on bomb. While a bomb in any crowded place is horrific, we should try to make an aircraft to be no more scary a place for one than any other crowded place, and needing no more security than those.