If you're taking a flight from Salt Lake International Airport anytime soon, you'll probably pass through a new kind of scanner designed to fight terrorism -- a whole-body scan that creates a black-and-white electronic image that looks a bit like you without your clothes.

Is that a minor nuisance or an intolerable invasion of privacy?

Freshman U.S. Rep. Jason Chaffetz says it's the latter, and he plans to introduce a measure in Congress limiting use of this new technology at airports. The Transportation Security Administration has been testing the machines at Salt Lake and other airports.

Whole-body imaging is just what its name suggests: It penetrates passengers' clothing to reveal guns, explosives or other dangerous materials. In the process, it also provides electronic images of passengers' bodies.

The images are screened in a remote area, so no screener connects an image to a particular person. Facial features and private parts can be blurred, and the scans are not saved.

But Chaffetz says it's nevertheless far too intrusive. He called it "TSA porn." His bill would prohibit use of the scanners as the primary way of checking passengers, though using the scans on passengers who set off a metal detector would still be allowed. People with implanted medical devices such as artificial hips or knees, for example, often set off the metal detectors. Such folks may prefer a whole-body scan to a pat down, an indignity they must suffer now.

Chaffetz is not the only one who has objected. He has found an unlikely bedfellow in the American Civil Liberties Union.

"Body scanners produce graphic images of travelers' bodies and are an assault on their essential dignity," said Barry Steinhardt, director of the ACLU's Technology and Liberty Project. "The safeguards announced by the TSA do not convince us that the technology is acceptable, and we question the supposed voluntary nature of these scanners."

Some observers worry about privacy in the long run, not just at the airport. The current machines have no capacity to store images, but Chaffetz's bill makes saving or sharing such an image a crime, which seems a reasonable safeguard. The last thing a celebrity needs is a computer image of his or her body making the rounds on the Internet.

Some have also criticized the government's obsession with security at airports. After all, there are many other targets that are more vulnerable.

Terrorism remains a threat, and the U.S. must try to stay a step ahead of fanatical groups like those behind 9/11. The new whole-body scanners might be a way to do that.

It's true that the images are very personal. Still, it's going too far to call the images pornographic. Moreover, the scans might reduce some of the frustrations and indignities of airport security. For instance, many people wouldn't mind if an electronic image appeared briefly for a screener if it meant they'd avoid other hassles like shoe removal or a pat-down.

But the bottom line is safety. The tested scanners include an advanced X-ray system designed to detect explosive chemicals. That in turn may help persuade TSA to drop its annoying ban on containers of liquids or gels in packages larger than 3.4 ounces.

In the testing so far, federal officials say, 98 percent of travelers have approved going through the scans. For instance, in Salt Lake, about 50,000 people have gone through the scanner, and only about 100 have refused.

What the scanner debate raises, however, is a bigger question: Are elaborate airport security measures really necessary? Or are they a diversion of precious resources from more effective counter-terror measures? After all, whole-body scanners cost $170,000 each and TSA personnel running all manner of other technologies (remember the now defunct air poofers?) cost billions more. Every one of those dollars is a dollar that cannot be spent tracking down terrorists and ferreting out plots in advance.

Is it really a necessary expense to use this sort of technology to screen grandma for high-explosives while cutting short efforts to break up terrorist cells outside the airport? Why does the government continue silly practices like confiscating pocket knives, scissors and knitting needles?

Perhaps whole-body scanners should be dropped along with a lot of other unnecessary and unproductive screening techniques. Anybody with a lick of common sense can scan the passengers at an airport and quickly rule out the vast majority as possible terrorists. Yet the indiscriminate screenings and confiscations go on.

What might be more useful would be some hard-nosed security personnel who can spot possible threats through database analysis and other targeted techniques. If instant background checks can be performed for gun purchasers, for example, they ought to be possible for suspicious travelers at an airport. Of course, this raises the problem of profiling. But the negative potentials in that might be fair trade for a more effective and efficient screening process.

There ought to be a way to ease the passage of the 99.9999 percent of people who obviously pose no risk without having their privacy invaded by a pat down, an electronic scan or any other intrusive -- and almost certainly unneeded -- measure.