Human Nature

Shanks on a Plane

The case for letting passengers carry knives.

Swiss army knives are displayed in a shop in Montreux, Switzerland.
Swiss army knives in a shop in … wait for it … Switzerland.

Photo by Fabrice Coffrini/AFP/Getty

Three months after 20 children were murdered in an elementary school, we can’t get even 40 votes in the United States Senate for a ban on assault weapons. But we’re going nuts over pocket knives on planes.

Members of Congress, backed by demagogues, airlines, and unions for pilots and flight attendants, are pushing a bill to stop the Transportation Security Administration from loosening its knife policy. TSA wants its screeners to stop confiscating pocket knives, golf clubs, hockey sticks, and other sports equipment from carry-on bags. The new policy would permit Swiss Army knives and other small blades the agency regards as harmless. The blades can’t lock or extend more than 2.36 inches. TSA says these knives are ubiquitous, don’t jeopardize planes, and distract screeners from more serious threats. But the “No Knives on Planes” lobby says any implement—even a golf club, hockey stick, or a metal butter knife—is too dangerous. Rep. Ed Markey, D-Mass., is mobilizing the anti-knife movement to boost his campaign for the Senate.

Markey and the flight attendants issued the same warnings eight years ago, when TSA decided to allow scissors, screwdrivers, and pliers on planes. “This is the equivalent of handing back the box cutters to the 9/11 hijackers,” Markey declared in a 2005 letter to the secretary of Homeland Security. Hillary Clinton, then a senator from New York, introduced a bill to stop the new policy. How many passengers since then have used any of the permitted items to threaten or attack anyone? Zero. A few years ago, the International Civil Aviation Organization, which guides security policy for many countries, recommended that knives with blades of six centimeters or less (that’s 2.36 inches) be accepted in carry-on bags. TSA Administrator John Pistole says 5 billion passengers have been screened under that policy, with no reported onboard incidents.

So why is TSA losing the debate on this issue? Because the case for relaxing the knife policy is ugly, callous, and scary. Nobody wants to spell it out. Here it is.

1. Sharp weapons are already on planes. Security experts know it’s easy to make a weapon using common onboard items. At a congressional hearing last week, Pistole pointed out that any passenger could simply buy and break a wine bottle. Former TSA chief Kip Hawley says you can make a decent slashing weapon with a soda can, a ruler, a key, and duct tape. Patrick Smith, the “Ask the Pilot” columnist, suggests a broken dinner plate, a plastic shard, or a sharpened pen. On the other side, the Federal Law Enforcement Officers Association claims that the fatal stabbing of a prison guard last month illustrates the peril of allowing knives on planes. But that story actually makes TSA’s point: The guard was killed with an improvised, plastic-edged weapon.

2. The danger from explosives is worse than you think. One common reaction to TSA’s decision (illustrated by this proudly ignorant Fox Business host) is disbelief that the agency thinks knives are safe but a bottle of lotion isn’t. The history of terrorist plots against U.S. air carriers over the last decade—shoe bomber, underwear bomber, toner cartridges—reflects a strategy of devising weapons that don’t look like weapons. And these weapons are designed not to slash one person at time, but to blow up a whole plane. The most alarming thing at last week’s hearing wasn’t any of the knife stuff. It was the veiled exchanges between Pistole and the committee chairman (“I cannot go into specific details in this open hearing”) about intelligence pointing toward “nonmetallic” explosives, some of which TSA was unprepared to detect. There was also talk of “internal covert testing” showing that small knives—Pistole said his screeners find 2,000 of them every day, and each one consumes two to three minutes of a screener’s time—“can distract our security officers from focusing on the components of an explosive device.”

3. Looking for ordinary weapons is a mistake. For years, critics have argued that U.S. screening of air passengers, unlike Israeli screening, wrongly focuses on detecting petty weapons (“security theater”) instead of identifying and tracking dangerous people. TSA’s knife decision essentially embraces that critique. It represents an explicit, broader shift toward “risk-based security.” At the hearing, Pistole said TSA is turning “away from the one-size-fits-all approach to passenger screening adopted in the wake of the 9/11 attacks.” He acknowledged, “In aviation security, it is not the object per se that is dangerous, but the individual who intends to use that object to inflict harm that presents the danger.” He told an angry congresswoman that protecting flight attendants from nuts or drunks isn’t TSA’s job. TSA’s job is to stop terrorists, and the best way to do that is to infiltrate them, snoop on them, track them, learn their methods, and focus on defeating those methods. After 12 years of making you stand in lines, surrender tweezers, and miss flights, the government is beginning to admit that, yes, this is a dumb way to stop terrorism.

4. We’re willing to let you die. In a March 9 letter to Pistole, Markey complained: “While reinforced cockpit doors make it harder for a terrorist to harm pilots or gain control of an airplane, they do nothing to protect the lives of the passengers and flight attendants in the main cabin.” Five days later, at his hearing, Pistole agreed. He testified that thanks to “hardened cockpit doors” and “the demonstrated willingness of passengers to intervene to assist flight crew during a security incident … a small pocket knife is simply not going to result in the catastrophic failure of an aircraft.” Yes, you might be slashed by a fellow passenger. You might even bleed to death. But flight attendants and other passengers will overpower your assailant. He won’t get into the cockpit and take down the plane. And to TSA, that’s what matters.

The reason the flight attendants’ union is upset about the new knife policy is that they’re the ones who are being put at risk. Eight years ago, when TSA allowed scissors on planes, the flight attendants complained that they would face the danger “while our pilot colleagues are safely behind barricaded flightdeck doors.” They were right.

The flight attendants claim that allowing knives on planes will lead to another 9/11. But as Smith, James Fallows, and other writers have pointed out, there won’t be another 9/11, because that plot depended on a level of innocence our country will never recover. The passengers on the first three hijacked flights of 9/11 could have overpowered their assailants, but they didn’t, because they thought the hijackers were going to land the planes, not crash them. Once the passengers on the fourth flight learned what had happened to the other three, they rushed the hijackers and overwhelmed them. By then, it was too late. We’ll never make that mistake again. If you pull a knife on a plane, your fellow fliers will tackle you.

If you want to ban knives to protect every passenger and flight attendant, fine. The Federal Aviation Administration can do that. But don’t drag airport security screeners into it. An aircraft cabin is no more sacred than any of the thousands of federal buildings and facilities that permit pocket knives with blades of less than two and a half inches. TSA’s job isn’t to make sitting on a plane safer than riding a bus or walking around a museum. It’s to keep planes from going down.