Disturbing news from the New York Times—the TSA says it plans to replace metal detectors at most US airports with backscatter x-ray machines:

Initially, the machines were supposed to be used only on passengers who set off the metal detectors, to provide them with an option to the customary secondary physical pat-downs and inspections by electronic wand. But Robin Kane, the agency’s acting chief technology officer, said that the initial results from pilot tests at some checkpoints at 19 airports in the United States had been so good that the idea of using the machines as the standard checkpoint detectors made sense.

Foremost, I maintain my objections on the basis of privacy and safety. But to replace a huge number of $3,000 metal detectors with complex, unproven machines that cost $100,000 to $170,000 each? How does one justify that in this economic climate? Say, for the sake of argument, that these machines could make airports 0–15% more secure. They still cost 4500% more! The era of “more security at any cost” is over—or at least it ought to be.