“Since the U.S. increased its use of body scannersl, terrorist groups have repeatedly indicated an interest in pursuing new ways to conceal explosives, said a U.S. security official . . . the best way to detect explosives inside a body would be through a full body X-ray, which is not used for airport screening because the dosage of radiation is too high.” –Los Angeles Times

Surgically-implanted bombs do not seem terribly likely, but the simple fact that they are being discussed and prepared for highlights a problem in the way we approach counter-terrorism. Understandably, people want to feel safe when we go to the airport. The best way to do that is to set up large, visible, intrusive obstacles to would-be security threats, such as metal detectors, pat downs, and scanner machines. These measures are evidently doing a pretty good job at making people feel safe. Despite some very vocal outrage, only 15% of Americans said that they believed that the Transportation Security Administration (TSA) should stop using “porno-scanners” last fall. Airport security measures make us feel safe, but do they actually deliver?

Full-body scanners are the most cutting-edge piece of anti-terrorist technology currently deployed at airports. Even so, Wired cited reports in March indicating that they “might not detect explosives or even guns taped to a person’s body.” One member of British Parliament who used to work for a company producing them claimed last year that scanners “probably would not have detected key plots affecting passengers in the UK in recent years.” The Times Union of upstate New York reported last December that scanners had successfully detected “small amounts of marijuana wrapped in baggies, other drugs stitched inside underwear, ceramic knives concealed in shirt pockets,” but that “the machines could miss something far more deadly: explosive material taped to someone's abdomen or hidden inside a cavity.” Not even the best technology is a failsafe against terror.

Terrorism is not confined to a few tactics. It would be a mistake to figure that if only we could create scanners powerful enough to see inside of bodies, we will have ended the threat of terror in the air. It would have been a mistake sixty years ago to think that if only we could create detectors capable of seeing metal underneath clothing, we would be rid of our every fear. Terrorism is a product of human ingenuity. Metal detectors were invented, so attackers use plastic and liquid explosives. Bomb-sniffing dogs are used, so terrorists started using plastic box-cutters. Body scanners were introduced, so they are considering implanting bombs inside of bodies. When X-ray machines are introduced, terrorists will outsmart those, too. Weaponry evolves in order to keep pace with security measures. The more we improve on our tactics, the more they improve on theirs. The idea of sewing explosives in next to internal organs would have been unthinkable even ten years ago. It came about as a result of advances in security measures. It seems that security is destined to play catch-up with terrorist innovation forever. The greater the leaps forward we take, the more extravagant the threats we will face.

Fortunately, there is one weapon that has to stay the same: the human weapon. No matter what an airline terrorist is wielding, there are some things that he will need in order to pull off an attack. Motivation, communications, training, and funding will serve as marks of terrorism long after we have invented the next generation of detection equipment, long after terrorists have found deadlier weapons to evade it. If the United States focuses more of its resources on identifying the people likely to bomb planes, rather than thinking up new ways to pick through the body cavities of flyers, we can win this arms race. We evidently know that al-Qaeda operatives in Yemen are talking about the possibility of surgically-implanted suicide bombs. If we can find that out, it stands to reason that we can find out who they spend six months training at camps overseas to send back here with detailed plans on how to cause the greatest number of casualties. Mr. Abdulmutallab knew enough about airport security to take the extraordinary step of sewing bombs into his underwear. Why did we not know enough about him to arrest him long before he ever set foot on Northwest Flight 253? Is it possible that we could have discovered him had we spent the resources we currently use groping passengers on following intelligence leads instead? There is no need to send bomb dogs back to the pound, or to abolish the TSA in favor of the CIA, but right now we need to stop escalating this arms race and start hunting down our enemies.

If the intelligence community does its job, it will probably fail to make us feel any safer. Ideally, we will never even hear about its efforts. But terrorists will always find ways around whatever highly-visible security barriers we put up. We ought to spend our time, energy, and money finding them, rather than pushing them to invent weirder, even more dangerous ways to kill us.