It's worth mentioning that while some of the alternatives to patdowns, such
as whole-body x-ray screening, are less obviously invasive, people
complain about them too:
American Science and Engineering in Billerica, Mass., says its "BodySearch" system reveals plastic guns and ceramic knives. Instead of simply sounding an alarm if it detects a metal object, it shows an X-ray image of the person on a computer screen. A company marketing photo shows that its scanning device reveals items hidden under clothing, such as plastic guns, ceramic knives, even drugs. But it also shows the man's buttocks and a blurry image of his genitals.A system from Rapiscan Security Products, a Hawthorne, Calif., company, uses a similar technology. The company's promotional photos show a man with a Glock 17 pistol tucked into his pants. They also explicitly show the overweight man's body.
The American Civil Liberties Union opposes the idea of using body-scanning devices on all passengers.
"These devices are electronic strip searches," said Jay Stanley, a spokesman for the ACLU. "To board an airplane, people shouldn't have to submit to strip searches and reveal intimate and potentially embarrassing details about their bodies."
Would you rather be groped by strangers or have them stare at x-rays of your genitals? Tough call.
For most people, I imagine it would depend heavily on the strangers in question.
It depends if you tolerate strangers taking "naked" pictures of your children or yourself.
In some countries, e.g. the United Kingdom this could easily be construed as the crimes of Voyeurism or of "making and distributing child pornography". Even if that is not the official intent when installing such equipment the potential for private abuse by security guards of such equipment is huge.
The only "advantage" of a pat down search from a privacy perspective is that the victim/subject is aware that is happening. This is not always the case with "see through your clothes" technologies.
If various technologies such as the current Passive Millimetre Wave or Low-intensity Backscatter X-ray, or future TeraHerz or UltraWideBand scanners and imaging devices become cheaper and more widespread, they will be deployed more routinely as covert surveillance devices. Covert tests have already been done, apparently on the streets of London, according to the Commissioner of the Metropolitan Police Sir John Stevens. At present these expensive units are only used in overt screening stations being tested at some airports and as portable units for mass screening of suspects rounded up in police raids. Bulkier and more powerful units are also being used to to check freight containers, with obvious potential health risks to humans if they are simply turned onto the crowded streets in order to detect hidden weapons or explosives or drugs.
c.f. "Passive Millimetre Wave Radar or other "see under your clothes" imaging"
Perhaps we could try looking for terrorists, rather than looking for weapons. Is that just too extreme, or is it too bizarre an idea?