Lost in the recent London bombings, along with innocent lives, was any illusion that today's surveillance technology can save us from evildoers. Britain has 4 million video cameras monitoring streets, parks, and government buildings, more than any other country. London alone has 500,000 cameras watching for signs of illicit activity. Studying camera footage helped link the July 7 bombings with four men -- but only after the fact. The disaster drove home some painful reminders: Fanatics bent on suicide aren't fazed by cameras. And even if they are known terrorists, most video surveillance software won't pick them out anyway.
Tomorrow's surveillance technology may be considerably more effective. But each uptick in protection will typically come at the cost of more intrusion into the privacy of ordinary people. For now, the public seems to find that trade-off acceptable, so scientists around the world have intensified efforts to perfect the art of surveillance, hoping to catch villains before they strike.
Research laboratories envision tools that could identify and track just about every person, anywhere -- and sound alarms when the systems encounter hazardous objects or chemical compounds. Many such ideas seem to leap from the pages of science fiction: An artificial nose in doorways and corridors sniffs out faint traces of explosives on someone's hair. Tiny sensors floating in reservoirs detect a deadly microbe and radio a warning. Smart cameras ID people at a distance by the way they walk or the shape of their ears. And a little chemical lab analyzes the sweat, body odor, and skin flakes in the human thermal plume -- the halo of heat that surrounds each person.
All of these projects are on a fast track since September 11. Meanwhile, consumer demand is speeding their development by lowering the cost of the underlying technologies. Camera phones, nanny cams, and even satellite photos are commonplace. Biological sensors are flooding into households in the form of tests for HIV, pregnancy, and diabetes -- some of which can relay data to a doctor -- and soon there will be far more sensitive DNA-based tests. Next up are radio-frequency identification (RFID) tags. They're showing up in stores to help track inventory, and 50 people in the U.S. have had them planted under their skin to broadcast their ID and medical data, in case of an emergency.
Together these developments herald a high-tech surveillance society that not even George Orwell could have imagined -- one in which virtually every advance brings benefits as well as intrusions. Rapid DNA-based probes, for example, could help protect us from bioweapons and diagnose diseases, but they might also reveal far too much about us to health insurers or prospective employers. The trade-offs are uncomfortable, in part, because corporations and governments will continue to wield the most advanced surveillance systems. But ordinary citizens will also gain capabilities to monitor their surroundings with consumer technologies, from Web cams to Net search and tracking tools, allowing the watched to observe other watchers.
One great worry is that those who stand out from the norm or express unpopular views, minorities, the poor, or just the ill-mannered, may get stomped in new and surprising ways. A recent incident in South Korea shows how this can play out. A subway commuter posted on the Internet some cell-phone photos he took of a passenger who had refused to clean up after her dog relieved itself during the ride. In no time, a vigilante mob on the Web identified her by her face and the purse she was carrying, and she became the object of national vilification. "You can move into a surveillance society one tiny camera at a time," says Deirdre Mulligan, director of the Samuelson Law, Technology & Public Policy Clinic at the University of California at Berkeley.
If terrorism becomes endemic in Europe and America, emerging surveillance tools may be abused in even more egregious ways. At the same time, the overhead burdens of a police state, from the dossier-building to the endless security checkpoints, could impose crippling costs on a free-market economy. Witness the U.S. clampdown on foreign student visas, which could end up crimping universities' ability to do advanced research. "We could bankrupt ourselves, much like the Soviet Union did," notes Kim Taipale, executive director of Manhattan's Center for Advanced Studies in Science & Technology Policy.
Experts disagree about when the most visionary tools to thwart terrorist acts will arrive on the market -- and whether they will deliver on their promise. Sensors that can detect bombs, radiation, and toxins exist today, and will be far more sophisticated a decade from now. But strewing them across every city in America would cost untold billions of dollars. High-tech electronic eavesdropping on communications networks can be effective, but only if terrorists use telecom systems. And even with improvements in cameras, biometric devices such as iris scans, bomb sniffers, and tracking software, it will be years before they can pick a terrorist out of a crowd. In short, the march toward a surveillance society may be inevitable, but no simple cost-benefit equation can assure us that the sacrifices will be worth it. We'll be debating the point for decades to come.