It is not often that The Economist pushes the product of a small company. But that is what it has done in its March 23 issue. It is fascinated by the Israeli company WeCU, headed by Ehud Gigon, which has devised a way of spotting “persons of interest” in airports that traditional methods miss, making it possible for authorities to have a serious chat with them. Mr. Givon says tests in both laboratory and real-life situations have shown that this method works in 95% of cases.
The idea is to display in the line of vision of approaching passengers stimuli – such as photographs and code words – that only terrorists know. There is nothing secretive about it – they are not concealed. These stimuli are supplied by intelligence authorities who know that they are associated with particular operations. The body temperature, heart rate and breathing rate of those who recognize them will change even if they are aware of the existence of the testing technology. Enud Givon’s apparatus will measure the changes. To non-terrorists the stimuli mean nothing. In their physiology nothing will change.
The advantage of this method is that the spotting is done by impersonal technology and is not dependent on subjective observation by possibly tired and bored security personnel. It has that in common with the polygraph, which, however, can only be used in cases that have already been selected, is cumbersome and time-consuming and has often been shown to be unreliable.
Airport authorities all over the world might be more interested in this new concept than the managers of the Ben Gurion airport in Israel. There, an eminently successful security system is already in place. Much of it is invisible to the passengers whose behaviour is monitored even before they enter the terminal. After they have arrived, in due course, psychologically trained security people chat with them and, if they discover anything suspicious, make arrangements for subsequent intensive questioning.
But even the Israeli authorities might benefit from WeCU’s innovative methods, if further testing confirms their effectiveness, because the technique is simple and economical.
The time may not be far away when thousands of travelers all over the world will be subjected to stimulating slide-shows on their way to the departure gate.
Eric Koch’s book, The Weimar Triangle, is available at Indigo-Chapters and in your local bookstore. 
Pearson Airport in Toronto handled 30 mllion passengers last year – so every day the security folks would have to pull out over 4000 people for investigation. Is that manageable?
Consider the number of attempted terrorist attacks on airplanes in the past 10 years – fewer than ten, worldwide. (The ones on 9/11 were spectacular, of course.)
Is that a good return on investment of security resources? (Much security is not interested in ROI, mind you, only in looking good to the scared but credulous masses.)
Israeli-style review of passengers does not work well with very large numbers of travellers, though it is good with the numbers that Israel has to work with.
You are saying that when you have a Pearson-sized airport any security system is as good as any other because all that matters is that the scared and credulous masses are reassured. I am sure you are right, although we don’t know how many,, if any, potential trouble-makers are actually caught – we assume NONE, but we don’t know. Or do we?