The U.S. Transportation Security Administration announced yesterday that it was delaying a plan to allow passengers to carry pocketknives, hockey sticks and golf clubs aboard airplanes.

With terrorism prominently in the news ― and opposition surging from flight attendants and others in the airline industry ― this decision was perhaps inevitable. It’s also wrongheaded.

To a public that has gone along with relinquishing hand lotions, bottled water and other seemingly innocuous items, it may seem absurd that the TSA was even considering allowing knives on board planes. To the contrary, it was an indication that, after years of trial and error, the agency was finally getting smart about security.

The prohibition against small knives is, first of all, ineffective. As the former administrator of the TSA, Kip Hawley, has pointed out, a terrorist could assemble a “12-inch razor-sharp sword” using a soda can, a key, a ruler and some tape. The current administrator, John Pistole, has said that a passenger could simply smash a wine bottle that he purchased on board. Small scissors and screwdrivers have been allowed through U.S. security since 2005 without incident. Other countries have allowed pocketknives since 2010.

Yet highly trained TSA screeners still have to devote time and attention to the 2,000 small knives they find every day. Each of these incidents requires two or three minutes to resolve. That’s no small hindrance. Every additional banned item that TSA agents must root through your luggage for distracts them from looking for what really matters ― nonmetallic explosives, which are a serious and evolving threat that could bring down a plane.

The proposed rule change wasn’t flawless. Knives that extended beyond 2.36 inches could still have been confiscated. Why a 2.37-inch blade would pose an enhanced danger remains obscure to us, and making this distinction would seem to undercut any timesaving advantage. As Hawley has argued, battle axes and machetes should also be approved under a logical system. “Bring anything you want that is pointy and sharp,” he told CNN, “because while you may be able to commit an act of violence, you will not be able to take over the plane.”

That may sound counterintuitive, but it’s an important point to understand: The TSA’s job isn’t to make sure that nothing bad ever happens on an airplane. Its job is to make sure that no one blows up a plane or intentionally crashes one into a building again.

You will probably hear people ― many of them in Congress ― point out that the Sept. 11 hijackers used box cutters to gain control of the planes they brought down. This may be true. But three things have since changed. Cockpit doors are now locked and reinforced. The Federal Air Marshal Service has been substantially expanded. And the flying public now knows to disarm potential hijackers ― as it did with the terrorists aboard United Flight 93 on Sept. 11, with the “shoe bomber” Richard Reid in 2001, and with the “underwear bomber” Umar Farouk Abdulmutallab in 2009.

The next terrorist who attempts to strike an American airliner won’t be fooling around with knives and box cutters, because they won’t work. He’ll use weapons that you probably haven’t thought of. In response, the TSA shouldn’t endlessly try to update a list of banned items ― it should focus on identifying dangerous people instead. That means prioritizing threats, sharpening intelligence, improving behavioral-profiling techniques and managing risks.

Ending the knife ban would have been ― and still can be ― a step in the right direction.

(Bloomberg)