Hey there, human — the robots need you! Vote for IEEE’s Robots Guide in the Webby Awards.

Close bar

A New World of Terror

What technology can and cannot prevent

6 min read

Staggering though they were, the coordinated attacks that left at least 5000 dead in New York City, Washington, D.C., and western Pennsylvania were a long-expected escalation in the deadliness of terrorist operations. Experts had been awaiting with dread the day when technology would let terrorists boost their murderous yield from a few hundred deaths to a number well into the thousands. That day arrived last 11 September literally out of the blue, a cloudless late-summer morning in the northeast United States.

The shock was the way the atrocity was carried out. Analysts were expecting that sophisticated weapons of mass destruction would take terrorists to the next level in their abominable craft. Hardly anyone foresaw that meticulous planning and ruthlessness, by exploiting an air security system gone terribly lax, could turn several airliners into a destructive force as lethal as a small atomic bomb or a perfectly-deployed chemical weapon–and with comparative ease and at a tiny fraction of the cost.

"They found the loopholes and ran right through them in a low-tech way," said John Parachini, the executive director of the Washington, D.C., office of the Center for Nonproliferation Studies of the Monterey Institute of International Studies. Indeed, the terrorists apparently carried weapons no more sophisticated than cheap razors and small folding knives. Not a single bomb blew up before the planes themselves exploded. And the provocateurs needed no more reconnaissance than a vague familiarity with the locations of the World Trade Center and the Pentagon.

At first glance, at least, it seems the array of counterterrorism technologies under development in the United States and elsewhere would have been useless to prevent the 11 September attacks. Neither airport detectors that can sense plastic weapons and explosives nor state-of-the-art sensors that could ferret out the chemicals, biological agents, or nuclear materials of mass destruction would have revealed the presence of murderous fanatics armed with box-cutters, familiarity with an airliner cockpit, and a determination to trade their deaths for many more U.S. lives.

And if the deed was, as is now believed, the work of terrorist cells that operated with a minimum of electronic communication among cells, there would have been little opportunity for technical methods, such as signals intelligence, to unmask the plot. After years in which technology appeared likely to make serious inroads in international terrorism, a new reality has dawned, one in which terrorism has demonstrated itself to be far more determined, adaptable, and resourceful than was previously imagined.

Nevertheless, that revelation does not suggest it is time to abandon or even curtail work on technical aspects of counterterrorism, analysts say. Rather, it is time to view technical methods and intelligence as part of what must necessarily become a far larger toolbox.

"Terrorists are nothing if not adaptable," wrote Stefan H. Leader, a security analyst and former consultant to the U.S. Department of Energy, in a recent report. "Shifting political fortunes and new antiterrorism measures will continue to force existing terrorist groups to reinvent themselves and new groups to find new methods."

"We have focused inordinately on the prospect of the use of unconventional weapons," added Parachini, referring to chemical, biological, and nuclear armaments. "Now’s the time for us to get the balance right."

It is increasingly apparent that–at least for now–terrorists have become disillusioned with chemical, nuclear, and biological weapons, experts said. Take Osama bin Laden, the Saudi-born terror mastermind suspected of directing the 11 September massacre: "He’s been interested in all of them to some degree," said Kimberly A. McCloud, a research associate in the California office of the Monterey Institute’s Center for Nonproliferation Studies. Through his organization, al Qaeda, bin Laden, who holds a degree in civil engineering, reportedly made repeated and wide-ranging attempts to buy nuclear materials and even entire weapons between 1993 and 1998.

For example, a former bin Laden aide, Jamal Ahmed al-Fadl, testified last February before the U.S. District Court for the Southern District of New York about bin Laden’s attempts in Sudan to acquire a sample of enriched uranium that apparently originated in South Africa. The testimony did not reveal whether the attempt succeeded.

A chemical plant in Khartoum, Sudan, bombed by U.S. forces in August 1998, was linked in U.S. intelligence reports to bin Laden. Technical intelligence based on a soil sample collected outside the plant suggested the facility was making a chemical known by the acronym EMPTA, whose only large-scale use was in the production of an extremely deadly nerve agent known as VX. A single drop of the thick, amber liquid on the skin can kill an adult.

Potent as chemical and biological weapons are, it is no simple matter to kill hundreds, let alone thousands, of people with them. "You need enormous volumes," McCloud noted. "You need laboratories and scientists. Then you have to pair that creation with an effective delivery system. It takes a lot more than just dropping a jar of anthrax [a common biological warfare agent] off the Empire State Building.

"To achieve with a chemical weapon the level of fatality that was achieved last September would take a huge infrastructure"–as opposed to a couple dozen zealots with some commercial flight training and knives.

The most successful chemical-weapons attack orchestrated by terrorists occurred during the morning rush hour of 20 March, 1995, in coordinated attacks on five Tokyo subway cars. To produce the Sarin nerve gas used in the attack, the terrorist group Aum Shinrikyo had assembled an enormous infrastructure, with large chemical research and production facilities, and dozens of scientists, doctors and engineers. The total death toll in the 20 March attacks was 13 people.

McCloud and other analysts wonder why bin Laden, with his technical background and presumed understanding of the technical challenges, bothered to pursue weapons of mass destruction. After all, they are costly and difficult to build and deploy. Their required and oftentimes sprawling infrastructure attracts the attention of authorities and becomes a target for investigation, pre-emptive attacks, or retribution. Biological and chemical weapons, moreover, are invisible killers. They lack the explosion and flames so crucial to the spectacular events and indelible images that sow anxiety and loathing far and wide. Said McCloud: "Sometimes I wonder if he [bin Laden] is not just doing it for show, just to lead us down the wrong path…to divert our attention and then catch us where we don’t expect it."

That is precisely why counterterrorist officials must not now ignore the threat of weapons of mass destruction, according to some analysts. "Just because someone uses an old terrorist tactic–a hijacking–to cause a much more deadly result doesn’t mean we don’t need to be concerned about a chemical, biological or radiological attack, or a cyber attack that would bring down some of our critical infrastructure," Michael Vatis, the founding director of the National Infrastructure Protection Center at the FBI, told IEEE Spectrum.

"If we limit ourselves to looking just at the types of attacks we’ve already seen, we’re going to leave ourselves vulnerable to different kinds of attacks," Vatis added. He said the 11 September attacks themselves prove his point. With many officials and experts preoccupied, on the one hand, with truck-bombs, and, on the other, with weapons of mass destruction, terrorists formulated a plan that involved neither. Car- and truck-bombs, the standard terrorist tool of the 1980s and 1990s, have become less common recently as concrete barriers have become ubiquitous in government centers. And though it only killed 13, the 1995 Aum Shinrikyo chemical strike continues to reverberate powerfully in counterterrorist planning scenarios–and technology-research funding. Of the US $13 billion that the Bush administration requested for counterterrorist spending for next year, $1.7 billion was earmarked for countering weapons of mass destruction. The only larger allocation was the $2.6 billion to be devoted to "critical infrastructure."

"I do think there is a huge role for technology in fighting terrorism," said Vatis, who now directs the Institute for Security Technology Studies at Dartmouth College. "We need systems that will let us detect whether a chemical or biological weapon is being carried in a cargo compartment of a truck or ship." [Editor’s note: see "Biological Warfare Canaries," in the October 2001 issue of IEEE Spectrum.]

It is even possible that technology will have a supporting role, at least, in preventing precisely the kind of hellish hijacking carried out on 11 September. The main preventive measures being put into place at press time–putting more armed sky marshals on airplanes and prohibiting knives on all flights–are decidedly nontechnical. But they might be complemented some day by radar-based systems that would stop an airliner from being flown into a building. Another possibility, face-recognition systems, are already in use at some casinos. These would attempt to pick out known terrorists as they passed through a security checkpoint. And an Anchorage, Alaska-based laser entrepreneur and pilot, James O’Meara, claims he could easily build a laser-based system that would temporarily blind any cockpit intruder.

Of course, such measures will simply close off one avenue to terrorist tragedy. In the wider, cat-and-mouse conflict, even the best technology, administrative measures, and foresight can alter the rules, but they can not end the contest.

This article is for IEEE members only. Join IEEE to access our full archive.

Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, podcasts, and special reports. Learn more →

If you're already an IEEE member, please sign in to continue reading.

Membership includes:

  • Get unlimited access to IEEE Spectrum content
  • Follow your favorite topics to create a personalized feed of IEEE Spectrum content
  • Save Spectrum articles to read later
  • Network with other technology professionals
  • Establish a professional profile
  • Create a group to share and collaborate on projects
  • Discover IEEE events and activities
  • Join and participate in discussions