This is not to say that the uniformed screeners aren't more professional than they were in the past or that their presence doesn't create a degree of psychological comfort, both for government officials, who can claim to be doing something to keep us all safer, as well as for those passengers who continue to believe that engaging in ritualistic shoe-removal gives them mysterious, magical protection against terrorism.

On the grand scale of things, though, that's all it is: magical protection.

In fact, outside inspectors have found, over and over again, that federal screeners perform no better than the private screeners they replaced. Since they inspect only passengers and baggage, not the airport and its perimeter, they haven't eliminated the need for other forms of law enforcement either. And even when they are doing their rather narrow job correctly, their impact is dubious.

By their own account, federal screeners have intercepted "7 million prohibited items." But of that number, only 600 were firearms. So, according to the calculations of economist Veronique de Rugy, 99.9 percent of intercepted items were nail scissors, cigarette lighters, penknives and the like.

Yet this mass ceremonial sacrifice of toenail clippers on the altar of security comes at an extraordinarily high price. The annual budget of the federal Transportation Security Administration hovers around $5.5 billion — just about the same price as the entire FBI — a figure that doesn't include the cost of wasted time. De Rugy reckons that if 624 million passengers each spend two hours every year waiting in line, the annual loss to the economy comes to $32 billion.

There also has been a price to pay in waste, since when that much money is rubbed into a problem with that kind of speed — remember, the TSA had only 13 employees in January 2002 — a lot of it gets misspent. In the case of the TSA, that waste includes $350,000 for a gym, $500,000 for artwork and silk plants at the agency's new operations center, and $461,000 for its first-birthday party.

More to the point, the agency has spent millions, even billions, on technology that is inappropriate or outdated.

In fact, better security didn't have to cost that much. Probably the most significant measure taken in the past four years was one funded not by the government but by the airline industry, which put bulletproof doors on its cockpits at the relatively low price of $300 million to $500 million over 10 years. In extremely blunt terms, that means that while it may still be possible to blow up a plane (and murder 150 people), it is now virtually impossible to fly a plane into an office building (and murder thousands).

By even the crudest cost-benefit risk analysis, bulletproof cockpit doors, which nobody notices, have the potential to save far more lives, at a far lower cost per life, than the screeners who open your child's backpack and your grandmother's purse while you stand around in your socks waiting for them to finish.

But, then, this isn't a country that has ever been good at risk analysis. If it were, we would never have invented the TSA at all. Instead, we would have taken that $5.5 billion, doubled the FBI's budget, and set up a questioning system that identifies potentially suspicious passengers, as the Israelis do.

Even now, it's not too late to abolish the TSA, create a federal training program for airport screeners, and then let private companies worry about how many people to hire, which technology to buy and how long the tables in front of the X-ray machines should be. But every time that suggestion is made in Congress, someone denounces the plan as a "privatization" of our security and a sellout.

Which is why I conclude that we don't actually want value for money. No, we want every passenger to have the chance to recite that I-packed-these-bags-myself mantra to a uniformed official before boarding an airplane.

Magic words, it seems, are what make Americans feel really safe.