But young males are more criminally minded in general. Was the underwear bomber really hard to detect: young male, traveling alone with no luggage and a one-way ticket. Better check on grandma instead! Seriously?

The real problem is "what you are testing" we are not talking about finding defects in tins of beans, which in theory are all made the same way, but humans. Who are all not only made differently they also unlike the tins of beans have the freedom to behave differently. That is a tin of beans cannot "chose" to look like a tin of carrots, but a human can "chose" if they wish to look how they please. So they can stop behaving in the way used by the testers for the profiling and behave in a different way.

The problem with profiling is, in effect it is based on statistical information from past behaviour either real or perceived. This perceived behaviour is only used by the tester because at some point in the past somebody who did not understand what they were doing decided it was the way to go...

Humans if they have to, will always be able to game the system, it's true not just of profiling but random security checks and CCTV or any other "static" security technique.

That is they will always end up failing against a test subject that can evolve in some way, irrespective of initial success.

We see this with CCTV systems initialy they work and criminals get arrested in high numbers. Then the "honeymoon period" ends with the smart criminals evolving their crimanal techniques to negate the advantage the CCTV gives the authorities. The less smart ones just move to another area and carry on in the same old way untill they run out of areas without CCTV. The stupid ones carry on the same old way in the same place and end up having their wings clipped in some way, untill they either wise up or die out.So on mass we see a fairly normal "under damped first order" response to a step change.

However nearly all terrorist acts can be divided into two types "one offs" such as 9/11 and "repeats" such as roadside IEDs. Reactive security systems are generaly of no use against "one offs" and only of limited benifit against some "repeats".

All static and quite a few dynamic security systems are "reactive" and thus will generaly fail with time. Reactive systems are basically "feed back systems" and in most cases (negative feedback) tend to be stable as they return to "zero". Non reactive or "predictive" systems are basically "feed forward" the problem with predictive systems are that they are inherantly unstable irespective of if the feed forward is negative or positive and except in very well bounded and known cases tend to "crash the rails/end stops".

As we have seen with "profiling" when you try to deal with rare cases that evolve you go from a reactive system to a predictive systems and errors get amplified quite quickly and you get them "crashing into the rails" with people "kicking back" with provable claims of "racism" etc.

With all control systems you also have to consider "delay" or "response time" it is fairly easy to realise that the systems the DHS-TSA employ have a very slow response time. Now consider the terrorist "one off" they usually have a very rapid response time thus they end up as a fast control loop within a slow control loop. They will thus always "self correct" much faster thus appear "normal" within the slower loop...

The result is they can "test the system" in various harmless ways and work out the DHS-TSA control loop conditions and stay within them.

We actually saw this with 9/11 where they tested and found out the only penalty for carrying box cutters was they were confiscated, but would normaly get through...

Provided terrorists can "game the system" and they normaly can (because they have "choice" and it's a simple "numbers game") then you cannot beat them with the sort of systems the DHS-TSA will put in place...

The base fallacy rate doesn't go up because you profile; it goes down.

Profiling doesn't mean to ignore others, but to provide a way to winnow the large pool to a more managable size.

The fact you say you can't profile "Muslims" is fine and no doubt true. You wouldn't always know. But young males are more criminally minded in general. Was the underwear bomber really hard to detect: young male, traveling alone with no luggage and a one-way ticket. Better check on grandma instead! Seriously?

Don't take this as criticism.

I agree TSA is security theater and should be abolished. However, any manager that you approach with a proposal that eliminates a bad solution will respond, 'Okay then, what do we replace it with?"

Like the Net, competent adversaries exist. They want to blow up planes and kill Westerners. They don't respect life in the traditional Judeo-Christian manner. We, as security people, must combat the real threat. So tell me - how?

Screen Muslims? You're right - won't work - too many people, too much time, money etc. Like IDS, too easy to evade.

Mandatory military training for all American citizens? Might work - be a lot more challenging to take over a plane loaded with passengers trained in hand to hand combat etc. Still might lose a few plane loads of people
though...

Enforce existing immigration laws? Don't hold your breath - at least not with this administration.

You're a smart guy - sure, let's all get behind Rand Paul and kick the lame TSA screeners to the curb (and increase the unemployment rate by half a percent). I'm all in.

Now, what do we replace them with?

=;^)

How does this view add to the whole cost-benefit tradeoff discussion?

Maybe I should've been more specific about the context being 'human lives lost in an airline incident'. I guess what I'm trying to say is that a cost-benefit analysis which potentially lets a terrorist through the gates, which will therefore lead to a loss of human lives, will never see the light of day.

Hypothetically, if an airplane incident kills all 200 people on board, could this absolute number not be achieved on other mass transport systems? Trains, buses, ships etc.. Is an incident necessary for society to snap forward and demand paranoid TSA type checks for each of these mass transport systems?

Is it possible that we place too much premium on human lives lost in an airplane incident? Could we lower the perceived value of human life or equate the risk of air travel to other forms of mass transportation?

@ Etaoin:

Pattern matching from an IT perspective is much easier that human behaviour.. My reasoning is that in the IT world, with just a few logged events (correlated) you have enough data to suggest a possible pattern.. The prediction models have obviously been tuned with enough events to justify a probable pattern.. However, human behaviour being so unpredictable (innumerable variables to factor) and the number of sample events being so few, the prediction models are infantile at best.. This is not to say that we should stop the effort, but it's early days still and the common air traveller is the guinea pig being used to improve the model..

The argument, I suppose, is that given hindsight and experience, could we slow down and think about how this should be done and implement a well thought out mechanism instead of jumping into action and implementing a poorly thought out mechanism. This brings us back to Cost-benefit tradeoffs. If the poorly implemented mechanism is capable of preventing/detecting all incidents, regardless of the cost, would society prefer to have this in place while the intellectuals work out a well thought out mechanism which will produce the same outcome, but at a lower cost?

My hypothesis is that society will bicker, but will happily cough up to support a zero incident solution, even though it's not the most elegant or best thought out..

The warning that I "will not always be cleared" appears to be yet another example of security theater, perhaps to lower my expectations. Well, my experience has so far proven otherwise.

Furthermore, it's completely silly to impose the notion of randomness on a person like myself who's been determined not to be a risk. If I wasn't a risk when I departed three days ago, I remain not a risk when I'm returning home. I should enjoy Pre-Check everywhere, all the time. To believe anything else ignores reality.

Bruce, your ideas and writings have influenced my career in many ways. But in this specific instance, I must disagree with you. My IDS, my IPS, and my firewall do not randomly select individual datagrams for enhanced screening. They look for patterns. Pattern matching is imperfect, but it works most of the time. Sam Harris is on the right side of this argument: pattern matching is the only way to make aviation security work. You often allude that the science of security applies regardless of what the object of protection is. So why in this particular instance do you deviate from your own positions?

I'd also like to have a discussion about Mayor Bloomberg's defense of the stop and frisk policies in NY. Is that more like El Al security (applying the stop and frisk in a limited area where there is a high probability of crime) or is it security theatre? Crime is down in NY, does that justify frisking 700,000 people?

"1) Human life is perceived to have the highest level of importance to justify 'zero threat tolerance'. This probably explains the paranoia behind the need to protect it 'at all costs', specifically in the context of the transportation sector where it makes big news. All trade-offs are therefore insignicant."

No, that is incorrect. To take a specific example *from*the*transportation*sector*, improvements to roads in many nations are in part explicitly decided on the basis of the number of lives saved, where each life is costed at so many thousands (or hundred of thousands) of dollars per life. If the dollar value of the lives saved exceeds the costs of the roading improvement, the project gets a tick. If the value and cost are about even it might get a tick. If the costs are far in excess of the savings, it probably won't go ahead.

Which makes sense.

If there are three possible projects which will each cost about the same but you can only afford to fund one of them, which do you choose? The one that'll save one life, the one that'll save 10 lives, or the one that'll save 100 lives?

In this life-saving decision the cost-benefit isn't insignificant, it is *everything*.

Jon

While this statement holds good in a general context, this discussion is specifically about the security of human life. A few thoughts..

1) Human life is perceived to have the highest level of importance to justify 'zero threat tolerance'. This probably explains the paranoia behind the need to protect it 'at all costs', specifically in the context of the transportation sector where it makes big news. All trade-offs are therefore insignicant.

2) An alternative risk assessment model for the protection of human life will always be ignored unless there is a change in the perception of the value of human life.. I don't think that's going to happen any time soon..

3) No government agency, particularly the TSA, is going to risk being seen as not doing 'everything they can' to protect human life. While their protective measures may amount to being 'security theatre', my guess is they will have to be seen as striving for 'absolute security'.. I sincerely doubt there will ever be a directive that accepts the ocassional loss of human lives in favour of reduced costs of protection.

The risk of not catching a terrorist, if 'randomized secondary screening' is approved, will be considered way too high to justify implementing that model.

Have I misunderstood this in anyway?

Harris's own words, in context:

We are at war with Islam. It may not serve our immediate foreign policy objectives for our political leaders to openly acknowledge this fact, but it is unambiguously so. —The End of Faith, p. 109

there is no set of beliefs … more imperiling of the future than the beliefs of martyrdom or jihad in the Muslim world which are central to the doctrine of Islam. —http://www.youtube.com/watch?v=j0pxN0DuMAE

I am one of the few people I know of who has argued in print that torture may be an ethical necessity in our war on terror.

Given what many of us believe about the exigencies of our war on terrorism, the practice of torture, in certain circumstances, would seem to be not only permissible, but necessary. —The End of Faith, p. 199

There is little possibility of our having a cold war with an Islamist regime armed regime … What will we do if an Islamist regime, which grows dewy-eyed at the mere mention of paradise, ever acquires long-range nuclear weaponry? If history is any guide, we will not be sure about where the offending warheads are or what their state of readiness is, and so we will be unable to rely on targeted, conventional weapons to destroy them. In such a situation, the only thing likely to ensure our survival may be a nuclear first strike of our own. Needless to say, this would be an unthinkable crime—as it would kill tens of millions of innocent civilians in a single day—but it may be the only course of action available to us, given what Islamists believe.

Whenever confronted with the irrationality of his arguments, Harris has back away from the controversy, but not his own words. Racial profiling will be no different. Though it is commendable that Harris gave Bruce an opportunity to respond at his own site, if Harris's past history is any guide, Harris cannot be expected to change his mind no matter what Bruce's arguments are.

What else can one conclude that Harris is a willfully ignorant and hateful bigot?

Because most people, even rational ones, want simple answers.

Sorry about the abrupt and odd end of my previous post to you above, it was not intended the phone I use does this occasional when I'm traveling in and out of poor signal areas or the keyboard driver takes a walk in the park.

So to backup a little and continue,

The solution in RTOS's is usually to well over resource, that is to have "normal loading" be less than one third of available system capacity in critical systems. That is spare capacity for normal operation is twice that of used capacity. This is seen as gross over specifing in just about every other field of endevor as the costs are ludicrously high and it appears to be grossely inefficient.

Why is it over specified well it's to deal with "random" behaviour of the inputs to the RTOS, if the inputs arive in a certain order in a certain time frame then the system cannot deal with the load and a critical input is missed and does not get responded to when it should. This is not the sort of thing you want in say your cars brakes and as the CPU/memory resources have near negligable cost compared to the rest of the system significant over resourcing is a negligable cost.

However we also know it happens in real life we see it happening all the time in the medical proffession. Mostly it gives rise to people with canncer and the like being seen to late and thus becoming terminal, but we also see it where patients get left on trollies in corridors and sometimes die of neglect. Not because the doctors and nurses are incompetent or callous but because they don't have the reesources to deal with cases in a timely fashion (it's something I'm accutly aware of because it very nearly killed me back in 2000).

Now as I've already said the TSA don't criticaly resource for normal loading they under resourse badly, this means that their systems regularly fail to function in a way that would support a truely random selection process. Thus the process ceases to be random and starts to be determanistic, it only looks random to a casual observer because different people take slightly different periods of time going through the various screening methods. What happens is only one person in ten can be fully screened, and the person who gets selected is the next person in the que not a random person from the next ten people at the head of the que. As Bruce has admitted in the past he has become quite adept at avoiding the scanners, and he is not the only high mileage passenger to do this, either conciously or sub conciously he is "gaming the system".

Thus at some point of overloading the system the determanistic pattern will become sufficiently easily visable and at which point it's game over for security.

An intelligently adversary (terrorist or smuggler) will be able to use the stogies to keep the pattern in place sufficiently long to ensure the carrier (of the bomb or contraband) gets through minimal screening.

We have actually seen this and worse happen with the TSA, there have been one or two reported cases of passengers who have triggered the detectors disappearing into the crowd air side because of other disturbances in the que side.

The chances are if two people started arguing, shoving or even fighting the TSA screeners would be "human" and become spectators or protagonists to the argument, thus another person could probably just walk through minimal screening without the TSA being aware they had. And as such would have bypassed any "random selection" process...

But the thing is a carrier does not of necessity need many (if any) cognizant stogies, they can "snow the system" with innocent and unknowing people. As an example the carrier has a single accomplice who quietly goes around the area of where the que end is covertly sparaying people with a week solution of drugs or nitrates etc as the people join the que. The result is the detectors start to show a lot of positives and the process starts to block. If done the right way then the overload on the insufficient resources will cause ordinary human responses from the TSA staff at which point you are back to pre 9/11 screening at best...

With regards this "out of place activity" of the sparyer is not easily seen by humans with short attention spans. However it has the same or sufficiently simillar charecteristics as a pick pocket or other type of criminal on platforms etc of public transsport and various systems have been designed and some tested to spot the re-occuring face in the crowd and then track it (mind you I've heard very little on the results of the tests which suggests they were not what was hoped for).

They had also planned on the non-response of the other passengers... ...That assumption is no longer valid, and everyone knows it.

And is compleatly irrelevant to the argument as is,

I ask you to perform the combinatorial analysis for having 20(!) terrorists... ...How many random screenings would it take to find a terrorist in that case?

Perhaps I did not make it clear,

The purpose of the (19) stogies is to do nothing more than to engineer the position of the bomb carrier in the que by gaming the system in various ways. They don't carry weapons or explosives or anything else that would pull them up as terrorists.

They game the system by silly things such as having a small coin forgoton in a back pocket or a chewing gum wrapper in their jacket pocket, by being slow tripping up or falling over by being rude complaining or argumentitive etc or even starting an argument / fight in the que.

It does not matter if they don't make the flight there sole purpose is to put a monkey wrench in the system to get the sole bomb carrier through the check point without being enhanced screened. and they do this by playing on the TSA's known behavioural responses.

As I said in my first post to you,

"All practical random systems can be gamed due to bias and constraints, which gives rise to the question of the resources required to game the system and the benifit derived".

From the terrorist point of view the "benifit derived" is getting a single bomb carrier through the checkin without being searched in a way that will reveal the bomb parts. The "resources required" are the number of stogies to achive that.

The hard part is working out the best time to have tickets for, how many stogies are needed and the methodology by which they are applied to the process of gaming the que to identify where slots will occur and how to time their disruptive behaviour to achive the "benifit".

Process and JIT designers have done quite a bit of assessment and theory on 'feeder stock" issues on ques relating to mechanical and chemical production and assembly and packaging of items from sub assemblies and component parts in a "just in time" system. The idea being primarily to minimise "on hand" stock costs.

Likewise there has been research done on "scheaduling" in "Real Time OS's" and this shows some very nonlinear results come up frequently and become critical and then at fault very very rapidly. One finding is the closer you get to full utilisation the more likely you are to get serious fails. The solution in RTOS's is usually to well over resource, that is have "normal loading" be less than one third of availab£llllllllllllllllllllllllllllllllll spare capacity for normal

Your claims are mostly based on the number of random screenings being large enough to exhaust the capacity of the screening system. There's no need to screen that many travelers, especially if the persons so screened are truly at random. That's the reason public opinion polls are very accurate, despite sampling a minute fraction of the electorate.

As for the rest of your claims:

"We know from 9/11 they had planed for four teams of five people or 20 people willing to die on aircraft that day."

They had also planned on the non-response of the other passengers, because that is what airline passengers (at least those of us in the US) had been told to do: do not resist, let the authorities handle it. That assumption is no longer valid, and everyone knows it.

"Thus it could be argued that 20 more could be found to die on a single plane flying within the US and that this would be sufficient to game the system to get one bomb carrier through."

While I disagree with your claim here, I ask you to perform the combinatorial analysis for having 20 (!) terrorists aboard an airplane the size of a Boeing 767 (or Airbus A330). How many random screenings would it take to find a terrorist in that case? Not many.

China has more Muslims than Syria, while Russia is home to more Muslims than Jordan and Libya combined.

http://www.pewforum.org/Muslim/...

It is extremely telling that Sam Harris associates "dark skinned" with Muslim. Really!

That goes to show how ignorant about any racial categorization he really is. He's even got a picture of an old woman (as an example of who *not* to racially profile) who could easily be a Muslim from one of over 20 counties, including the balkans, lebanon, turkey, chechnya, russian, afghanistan, etc.

Secondly, the average American has no clue as to race, and is much more ignorant of say the different races in Europe, then the Europeans themselves. Moving on to the middle east, Moving on, "Indo" refers to India and even within India, the Aryans of India (all 600 million of them in the North) are entirely different, racially, than the 500 million or so Dravidians in South India. Semites are entirely different than Indo-European people and Semites can be Christian, Muslim or Jewish.

The average American is totally lost and cannot tell the difference between any of these groups, so racial profiling, even if it was the best idea in the word, is totally doomed. It is ridiculous in a country like the USA which doesn't have any deep seated racial boundaries like the rest of the world and a complete inability to identify people from various races, let alone a blonde lebanese woman (christian, muslim?), blue eyed caucasian muslim, green eyed afghan muslim or a darker looking Indo-European hindu.

. Screenings must be random, because that is the only method which cannot be gamed by attackers.

Sorry but that's not true.

All practical random systems can be gamed due to bias and constraints, which gives rise to the question of the resources required to game the system and the benifit derived.

The constraints on an airline checkin are the closure time of the departure gate and the available screening resources and the time it takes to screen an individual through each one.

Screening resources are finite in number and take a certain minimum time to process an individual this provides a basic threashold of passenger numbers that can fully randomly be dealt with.

The threshold is fairly easy to work out as it's the throughput at 100% screening thuss if you have five machines and it takes two minutes to process each person five people can be fully screened in two minutes or one person every 24 seconds. At a rate higher than this some people can not be screened, the greater the rate the larger the number of people who cannot be screened.

There is a time based deadline by which the passengers must be screened otherwise the flight will not take off (there is the requirment that checked luggage must have the passenger on the flight to prevent other types of terrorism).

Thus there is a finite time between lugage being checked and the passengers being checked for the flight to happen.

The resources for checking passengers are very very expensive and are thus rationed to a point chosen by the checking authorities concerned. The minimum resource level to work would be that of 100% passenger checking at the rate of full passenger occupancy on all the flights leaving in the given time frame of airport operation.

You thus have two conflicting requirments, the airport and airline operators make profit by large passenger flows thus having high numbers of plane departures. The checking authorities want to minimise expenditure on expensive resources.

The result at best is "critical resourcing" more normal is "under resourcing".

Now the airport has busy and quiet times so at busy times the checking system is going to be very much under resourced.

This means it is not possible to 100% check all passengers therefore a finite number must go un checked. Thus a fully random system which can only work with critical or above resourcing is not going to work. The more under resourced it is the more determanistic in nature it becomes thus the easier it is to game.

One way to game the system is to pick a time to travel when way above average passengers are expected (thanksgiving / christmas) then throw a monky wrench in the system by creating extra delays in the que. By having two or three "stogies" (accomplices) ahead of the bomb carrier causing significant blocking of the resources the bomb carrier gets a very increased probability of getting through un checked. This works because the checking authorities cannot have more than a very tiny number of people missing their flights because the whole system would colapse as airplanes have to have luggage removed etc.

The question then becomes how many resources (stogies) does the terrorist need to use to increase the odds to near certainty of being unchecked?

We know from 9/11 they had planed for four teams of five people or 20 people willing to die on aircraft that day.

Thus it could be argued that 20 more could be found to die on a single plane flying within the US and that this would be sufficient to game the system to get one bomb carrier through.

Only we can be reasonably certain there are not that many suicied terrorists available in the US currently because they would have attacked by now.

In fact it could also be reasonably argued that if there were suicide bombers available in the US they would be waisting their effort to attack planes they would get better returns on blowing them selves up in city metros etc because this would cause the cry for TSA style screaning to be put in metro stations. The result obviously would be more devistating than an increase in airport screening. New York for instance would come to a stand still as there is probably not the "sidewalk" space to allow everybody to walk to work...

Sam Harris is a great writer and thinker, but he seems obsessed by the threat one religion poses, not the overall threats irrational behaviors of all kinds pose. And proper threat assessment is Bruce's area of expertise, as we all know.

I thank both of them for having this discussion in public for us.

Here's an observation: A good chunk of the TSA workforce are multi-ethnic. At oen point, I could have sworn that 90% of the ones I came across at this one airport (would rather not say) were Ethiopian. While many Ethiopians/Eriterians are not Muslims, they fit the "profile."

Now here's my question: What if a Muslim who cleared all background checks wanted to be a TSA agent? I'm baffled by the whole notion of being afraid of what one doesn't know; but I don't want to get preachy here. But seriously ... go and learn about Islam. Don't just listen to the media. Islam & Muslims will always be under attack. They hold the key to the start of all civilizations as we know it. And they are at the heart of the World geographically. And most of all, they control the World's wealth (oil). Of course, they're going to be under attack. I guarantee you if that part of the World was all that religion/culture would still experience the same crap.

Back to my point ... Muslim as a TSA agent. I'm going to guess that many [intelligent] individuals said "no problem." Let's go with that. What if that Muslim TSA agent was a woman who's exercising her choice to wear a Hijab (head scarf)?

Let the prejudice out. If YOU are OK with it, imagine the reactions she's likely to get to stop non-Muslims based on behavioral profiling; as it was suggested by many.

Let's take this farther a bit ...
How is a Muslim TSA woman agent with a Hijab on doing her job wanting to inspect a nun (I want you to imagine this at an airport in the South) different from a white biker all-tattooed-up white TSA man doing his job wanting to inspect a Muslim woman wearing her Hijab? Don't imagine a physical inspection, but the scrutiny, questioning and/or inquiry itself.

What's my point? It's out prejudice wrapped tightly in ignorance that's causing a problem. Combine all that with a hint of foreign policy positions/stands we take and we're going to be attacked by those of equal intelligence (or lack thereof).

I almost think of it as dumbass on dumbass war. Unfortunately, many of the rest of us are caught in the cross fire.

The only way it could profile would be not inspecting foreign looking people as closely, and they won't make that mistake again.

I think you overlook one point, which is not the central point of Sam Harris' narrative, but very much follows from his writing and is an important one.

If you enumerate the number of children who can very safely be determined to be non-Muslim, it will be a large percentage of children passing through security every day. The name and identity of his or her parents who are accompanying the child gives a huge discriminatory signal. Similarly, if you enumerate the number of physically disabled people and older women who are most clearly non-Muslim (color of skin, features, plus name on identification) passing through security, you are bound to find the number is an appreciable majority. It makes no sense to screen these people beyond the basic non-nudie-machine hand luggage screening and obvious metal-object-carried-on-person detection.

For a start, we can reduce the number of people put through this extensive screening procedure greatly. Once this starts happening, the security personnel can make exceptions for people not in those groups based on judgement and behavior.

No system can be perfect. This approach introduces both enough theater and enough basic screening all around that it will save huge amounts of money and resources while not being any worse. It is too much to expect a digital change to pre 9-11 security in the secure areas of airports, and this explicitly discriminatory system gets the best of both worlds: paranoid, non-highly-analytical satiated-by-security-theater on one hand and the Muslims-asked-for-it-and-need-to-deal-with-it Sam Harris and me types on the other.

This could be a transitionary step towards what you suggest.

That way you know it wasn't (necessarily) your fault for forgetting some piece of metal in your pocket.

Perv scanners are not used here as a field-test in Hamburg has found them to be useless.

What terrorists want is to cause the United States to spend so much money and piss so many citizens off that they have to change their political policies.

To that end they are still milking 9/11 and succeeding beyond their wildest dreams at "administrative jiu-jitsu"; ie causing us to use our own money against ourselves.

At the current rate of intelligence drift they wont need another attack on US soil for probably 15 more years and will still be bleeding us dry the entire time without lifting a finger.

The biggest threat the TSA is to AQ is to cause them to injure themselves through laughing too hard at our antics.

Oh man, the Balkans would really freak Mr. Harris out.

... so presumably it has been shown to work.

This is what I call the elephant powder fallacy, Peter.

A farmer walks up to his neighbour who on a daily basis is dispersing huge quantities of a strange looking, pink powder and asks him what it is for. "To keep elephants away from my land", he replies. In utter disbelief, the farmer tells him that there are no elephants anywhere in the region. To which the neighbour replies: "I know. This is really terrific powder."

Some nationalities need visas to fly to the USA (which leads to additional security checks, including an interview in person) and some do not.

Is there any hard evidence that this is counterproductive, in the way that Bruce's argument would suggest?

Although the plural of anecdotes is not necessarily data, there was an incident in August 1972 involving El Al and security and non-Arab threats. Two Palestinian individuals, Adnam Ali Hasham and Ahmed Zaid, gave a tape recorder to a pair of young English women who were going to travel to Israel. The women did not know that the recorder was rigged with a barometric-triggered explosive charge. As the recorder went in the womens' checked baggage, the resulting explosion was contained by the plane's armored baggage hold and the plane landed safely. (Source: One Day in September: The Full Story of the 1972 Munich Olympics Massacre and the Israeli Revenge Operation "Wrath of God" (Arcade Publishing, 2000), p. 38.) (It could be argued that being asked to carry an item by someone else is a cause for suspicion, but it is possible that such advice came about later on.)

You are constantly singled out by the police you don't go to the police for any other crime. You go to some neighbours of the same religion who will sort it out, then in return they might want you to store a package, or let some 'friends' stay with you in London, or provide an alibi for someone.

Add in a few police shootings of people who were the wrong religion and within a couple of decades you can turn an ancient religous argument into a civil war.

On the positive side you do end up with an anti-terrorist squad that is even better than the Isrealis

"and even if TSA screeners could identify a group
with no false negatives," = those found on being searched to have bombs.

"subjecting the people who fit the profile to extra inconvenience
is pretty morally questionable."

Amost Everyone wants a personal argument exemption.
Does anyone bother with reasoning anymore?
Bruce is largely right about Security Theater,
but suipport with weak and/or false logic undermines his position.
What we all need is to rigorously articulate
sound logic in his support.

You can ask someone their religion, but if it's clear that everyone who answer's "Muslim" gets stopped, no one will answer "Muslim".

So you end up profiling based on skin color, accent, nationality, etc.

Extra screening at random might make you mad at the TSA, but extra screening because you're in the wrong ethnic/religious group separates you from the rest of society based on a trait that has caused a lot of division in the past and continues to do so today. Screening based on some other trait like "blue eyes" just doesn't feel the same, either to those being pulled aside or those watching.

Imagine going through airport security where you (assuming you don't fit the profile) just breeze through. And off to the side, in a roped off area, you see the TSA giving more intensive screening to people who look like they're Muslim. I can't imagine such a scenario wouldn't feel pretty humiliating for the people pulled aside, and I also can't imagine it wouldn't damage the social relationship between the people who fit the profile and those who don't. Separating society into "us" and "them" is rarely a good idea.

Absolutely splendid essay that should be a mandatory read for anyone involved in airport security. This is the kind of stuff for which I keep coming back to this blog.

Personally, I believe that efficient, behavioural profiling can be a useful control in a defense-in-depth approach, but given the history of the TSA it is far more likely to be turned into an expensive travesty as they have done with most of their security theatre. It has already been argued on several occasions here that El Al profiling does not scale well to the US. That is of course unless the military-security-industrial complex can convince US Congress to fork out even more tax dollars at the expense of healthcare, welfare and education budgets.

OT @ Clive

The Greek approach to the coin problem would probably be to smooth talk the doctor into lending him the coin and then have him burn his fingers on it.

Yep. Which is why I like Bruce's idea of putting additional funding into services such as police that can yield benefits when terrorists do NOT strike. But can also help when terrorists DO strike.

"And of course the ultimate question is, why would a terrorist want to attack a plane?"

With a bomb? Because it is the easiest way to take out some Americans on American soil. But only if the terrorist got on the plane outside of the USofA.

If the terrorist has to negotiate airport security inside the USofA that is a different issue. And at that point it would probably be easier for the terrorist to start a random shooting spree in a city. Or to drive a car bomb into the airport. Or bribe a TSA person to let the "drugs" past. Or a thousand other options. All of which could be ameliorated or mitigated by having additional spending on police and such.

Arguing about which level of security is effective is kind of like wondering whether or not you should buy tidal wave insurance in Kansas. Absolute security is impossible, and anything beyond minimal has staggering cost-benefit & diminishing returns problems.

And of course the ultimate question is, why would a terrorist want to attack a plane? Once you understand that, you become FAR better able to assess the actual risks. But that is a Topic that Shall Not Be Raised.

...Or the cheeky person intentionally grabs the coin again and again to make the doctor write down he is an imbecile..in disguise.. "check that moron off the profiling list" :)

On a more serious note good points bruce and commenters.

I think any well thought out terrorist attack on air-travel systems would begin with targeting the employees and hiring process of the TSA. It would be an operation spanning different sectors of the "air-travel experience" (check-in, baggage screeners, airport security, management, etc.). If people aren't necessarily fit for security and underpaid, that is a gaping hole in security. It would take years to develop rapport, perhaps rise up the ranks a bit. Not a novel or easy-to-carry-out plan, but one where high emphasis should be placed, as there are currently many many new TSO jobs available...

We are not seeing attacks on the scale or frequency that makes these security-policies justifiable. I'm still waiting patiently on "the big one" that catches everyone with their pants down and will make these current procedures seem like "the good 'ole days"...

El Al doesn't racially or ethnically profile. So some 'expert' says its good idea - that doesn't mean a thing.

I don't know where you live, but as an American, I can find you a dozen policy 'experts' at my local university that no-one ever listens to.

That is because it is completely false that they use ethnic or racial profiling. The fact that you're neither young or Muslim has nothing to do with why they stopped you.

Better yet, start a petition for Bruce to be hired as Director of the TSA under the new administration. He certainly cannot do any worse (other than increasing unemployment when he fires some portion of their 58,000 employees.)