For an illustration of pure rationality that has become irrational, pass through any Canadian airport's security screening.
These procedures have been designed by civil servants at Transport Canada - not the Canadian Air Transport Security Agency, whose staff must apply the procedures.
The procedures are an example of pure rationality: Every threat, no matter how great or small, no matter its origin or seriousness, must direct the entire system. There is no threat assessment, therefore - no risk management. If one threat exists somewhere, threats must exist everywhere, so the maximum threat assessment must prevail at every airport, all the time.
This approach by airport staff was recently summarized by a senior U.S. security supervisor who told The New York Times: "I want them to think Abdulmutallab with every pat-down." He was referring to a Nigerian, Umar Farouk Abdulmutallab, who boarded a Detroit-bound airplane last December, allegedly intending to use plastic explosives in his underwear to blow up the plane.
This incident produced new spasms of alarm, with system-wide implications: body-scanning machines in the United States (dutifully followed by Transport Canada), pat-downs of selected travellers, heightened overall vigilance.
In both countries, the idea seems to be that every traveller must be treated as a potential worst-case scenario, a starting point that leads to the rational consequence that every security caution must be taken against all travellers.
And so, belts come off or belt-buckles are undone, shoes are removed or checked, arms are raised and now, the sprouting of full-body scanning machines. Everyone is a threat - the U.S. security official's apparent belief - with the result that 80-year-olds with wheelchairs or canes, or young children travelling with their families, are given the full treatment, inspections and all. No exceptions, no risk assessments, no judgment - all of which, of course, would be the antithesis of rationality.
A vast army of security inspectors has been created at all airports, the cost of which is paid for largely by travellers. The inspectors' job, presumably, is to keep travellers safe against the ever-present menace of terrorism in the air.
This army, however, is trained to fight yesterday's battle, courtesy of the shadow of 9/11. The most recent and dangerous terrorist attempts in the United States have come not from the air but from home-grown threats at New York's Times Square and in Portland, Ore. It would be so much easier for a suicide bomber to hit prominent U.S. targets by means other than an air attack that one wonders about the rationality of concentrating so many resources on just one potential vulnerability.
Certainly, this airport security industry has been a job-creator, but it has also been a monumental hassle for travellers, a colossal time-waster and an example of the rational being carried to irrational extremes.
Canada could chart its own course, at least on flights within Canada or to destinations other than the United States - assuming the Americans continue to insist on their excessive requirements - but Transport Canada, and presumably therefore the entire federal government, is afraid to do as Australia does.
Australia is just as concerned about terrorism and safety as Canada. It lost many citizens in a terrorist attack in Bali, broke up a dangerous budding ring of terrorists in Sydney and is anxious to remain on Washington's good side.
But instead of turning up the juice with screening machines, the Australians turn the juice down much lower, then randomly select passengers for a swab check. They operate on the far more sensible assumption that not everyone is a threat or should be treated as such. Just in case, they use random selection as a backup. Lines are shorter, costs are lower, delays are rarer and the country is just as safe.
We have, ultimately, a political problem with this irrationally rational approach: namely, that no politician wants to be accused of being soft on security, just as none wishes to stand accused of being soft on crime, even if most of the proffered "tough on crime" measures range between useless and counterproductive.
Sensible judgment gives way to the fear factor that should anything happen, the politicians will be blamed. Every politician's nightmare is to be blamed. And fear interferes with rational judgment.