Tomorrow's surveillance technology may be considerably more effective. But each improvement in technology will typically come at the cost of more intrusion into the privacy of ordinary citizens. The public in general seems unaware of the goals of scientists around the world who have been intensifying their efforts to perfect the art of surveillance, hoping to catch criminals and terrorists before they strike.



Research laboratories foresee tools that could identify and track just about every person, anywhere and sound alarms when the systems encounter hazardous devices or chemical compounds. Many of these ideas stem from the annals of science fiction. For example, 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 ?finger? people at a distance by the way they walk or by the shape of their nose. Chemical lab's analyzes the sweat, body odor, and skin flakes in the human thermal plume which represents the halo of heat that surrounds each person.

Consumer demand for video and audio surveillance products is speeding their development by lowering the cost of the underlying technologies. Camera phones, nanny cams, and even satellite photos are commonplace and can be found everywhere. Human 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 to be even more accurate matching than ever. Groups are working on radio-frequency identification (RFID) tags. These surveillance tags are sold 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.

These developments portray a high-tech surveillance camera society that could not have even been imagined by science fiction writer George Orwell, a world in which virtually every advance brings benefits as well as personal 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 not pleasant, in part, because big corporations and governments will continue to wield the most advanced surveillance systems. But also, ordinary people will also gain capabilities to monitor their home and surroundings with these advance consumer technologies, from Web cams to Internet search and tracking tools, allowing them to watch and be watched from every perspective.

Here's an example of what could happen in society: A subway commuter posted on the Internet some cell-phone photos he took of a passenger who had refused to clean up after her cat relieved itself during the ride. In no time, a vigilante mob on the Internet identified her by her face and the purse she was carrying, and she became the object of national vilification.

If terrorism becomes pandemic in Europe and America, emerging surveillance tools may be abused in even more bizarre ways. At the same time, the overhead burdens of a police state could impose crippling costs on a free-market economy. Witness the U.S. clampdown on foreign student visas, which could end up crimping a universities ability to do advanced research.

Industry experts disagree about when the most advanced tools to thwart terrorist acts will arrive on the market and whether they will even deliver what they 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. But even with the latest improvements in spy cameras, biometric devices such as iris scans, bomb sniffers, and tracking software, it will be many years before they can pick a terrorist out of a crowd and stop him before he commits his terrorist acts. Sacrifices in society and in governments will be made as our society becomes a surveillance society. The debate will rage on for decades to come.

The Ultimate Universal Sensor, a small and cheap enough to scatter in public places, and smart enough to sniff out anything that comes its way, without being preprogrammed to find specific molecules. Nobody is close to reaching that goal yet, but Sandia National Laboratories has designed a lab-on-a-chip that detects a variety of both chemical and biological agents. It has skinny micro channels etched in its surface. When a gas or liquid moves through the tiny pipes, it collides with special material, and how much that slows the flow betrays the identity of the fluid. Sandia is now developing this technology to monitor the Contra Costa County (Calif.) water supply.

These systems may not be in place in time for the next attack in a Western country let alone in Egypt or Iraq but if terrorists hit the U.S. again, the authorities are bound to strike back. Among other things, today's restraints on racial profiling are likely to crumble. Then what will we do? In the arms race against the terrorist suicide bombers, will surveillance technologies prove their worth?

Some governments have already used Electronic Monitoring to foil some terrorist plots, and portals that spot guns and explosives make airports safer. Unfortunately, many of the most powerful technologies are simply too new. It may take a decade or more before networks of biochemical sensors are ready to blanket a whole city. And it could take as long before camera systems can pick a known face terrorist or otherwise out of the crowds. For now, only a combination of electronic monitoring and human intelligence stands a chance of holding radicals at bay.

In the meantime, scientists who labor on surveillance prototypes are encouraged that their innovations can bring benefits in health care and food safety. Over time, people may get smarter about how to live with threats and make use of technology without undermining their most basic values. A country that sacrifices its citizens' freedom in the fight to protect them is no hero.