Airline Safety

By Dave

Recently, Spencer Ackerman made a pretty excellent point: Since the data to pull Umar Farouk Abdulmutallab was "very thin," the Christmas Day incident seems more like a policy failure than a intelligence failure. Essentially the policy worked as intended because it's designed to trade some security for liberty.

So the question is, I guess, is the policy what it should be? Do we need a better policy? Are the trade-offs what they should be? I've been thinking a lot about this but I haven't really come up with any answers, just lots of thoughts and questions. So I mostly present this as a kind of discussion topic.

The first question you have to answer is what what would be an acceptable level of safety be? How many false positives would we be ok with if it meant that we could be safer? By that I mean, what if we were more strict with who went on no-fly lists, just to be safe. We would be more confident that someone who posed a potential danger would be kept off the flight but we would also have to live with more innocent people being kept off as well. Yglesias uses Bayes's theorem to make this point:

...monitoring the UK’s 1.5 million Muslims is a lost cause. If you have a 99.9 percent accurate method of telling whether or not a given British Muslim is a dangerous terrorist, then apply it to all 1.5 million British Muslims, you’re going to find 1,500 dangerous terrorists in the UK. But nobody thinks there are anything like 1,500 dangerous terrorists in the UK. I’d be very surprised if there were as many as 15. And if there are 15, that means you’re 99.9 percent accurate method is going to get you a suspect pool that’s overwhelmingly composed of innocent people. The weakness of al-Qaeda’s movement, and the very tiny pool of operatives it can draw from, makes it essentially impossible to come up with viable methods for identifying those operatives.

So there's the rub. Even if we are really good at catching people, we still net more innocent people than bad. The more strict we make the requirements, the more innocent people harassed. This is a problem not only on moral grounds but also because harassing innocent people requires time, effort, and resources that should be going somewhere else. The problem is the system is better at punishing law-abiding people than it is at catching the bad guys because there are so few bad guys. However, bad guys are really good at causing disproportionate injury to society. On September 11, 18 guys with box-cutters were responsible for the deaths of thousands. So the costs of letting even a few people through the cracks can have disastrous consequences.

So how do we balance liberty and security? A econ-type might be tempted to say we identify where the marginal cost/benefit of being free equals the marginal cost/benefit of being safe. But the point at which these lines cross may not mean zero terrorist attacks. In fact, it's likely that there in an implicit level of insecurity people would be willing to live with if the trade-offs were made clear. But it's totally unfathomable that any policy maker would look the public in the eye and say that any amount of terrorism is acceptable. So where do you go from there?

Personally, I think the answer is technology. Especially if it means having shorter lines, fewer false positives, and more bad guys caught. If the airlines won't do it, the government s ultimately gong to have to step in on this. We need to invest in the liquid-explosive detecting machines. We should invest in better scanning technology. I personally don't mind the full body scan. I don't really care if some TSA worker get to see a vague outline of my nether-regions. Obviously, I get where the ACLU is coming from. But how about we make two lines: the quicker one where you get a body scan and move on, and the one where you get to take off your shoes, belt loose change, etc and mess around with all of your stuff . Let people choose which one they want.

Part of the problem is we haven't explicitly stated where our priorities are as a society. We haven't had an open conversation about where our priorities lie. Not that one could really expect to, in this polarized political climate, but still...

Any thoughts on this? Where do you come down? How would you balance liberty and security? What types of measures are acceptable for you and which are not?