Imagining Terrorism: Bombs Not Nukes, Guns Not Germs

By David K. Shipler

After 9/11, we blamed ourselves for lacking the imagination to think that hijackers might drive jetliners into buildings. To compensate for this failure, we expanded our imagination to picture terrorism by nuclear, chemical, and biological means. Now a carefully researched study concludes that weapons of mass destruction are unlikely to be used by jihadi terrorists. Their goals are more attainable with explosives and firearms, and the skill and equipment needed to mount an unconventional attack are far beyond the reach of existing terrorist groups.


The 78-page report, by the Breakthrough Institute, comes at the same time that scientists have agreed to a government request for a 60-day suspension in researching the mutation of the deadly H5N1 flu virus, lest its more contagious form “accidentally leak out of a laboratory, or be stolen by terrorists, and result in a devastating pandemic,” The New York Times reports. As depicted in the Breakthrough study, however, terrorists might not be interested in weaponizing such a virus, because it wouldn’t produce the spectacular events that “deliver compelling visual footage” for television. People dying invisibly in hospitals don’t further the aims of these groups, the study argues.

A sophisticated logic leads to that conclusion. Virtually all attacks and foiled plots since 9/11 have involved explosives and assault weapons. “No nuclear or radiological attacks have been attempted. No biological attacks have been attempted. No large-scale chemical attacks have been attempted.” Neither plans nor actual attacks have targeted food supplies, reservoirs, nuclear reactors, chemical plants, or other such installations, but rather “symbolic buildings, transportation targets, and other government assets.”

Why? One reason is that al-Qaeda and its offshoots “perform for three audiences: their potential supporters, the populations and governments whose behavior they wish to coerce, and their own membership.” In predominantly Muslim countries, they strive “to replace secular regimes . . . with fundamentalist Islamic theocracies,” requiring large-scale recruitment of “broad swaths of the Muslim population behind their goals.” This is “a war of ideas with the state,” a strategy to show the government as vulnerable and to “provoke state repression that negatively impacts the people the revolutionary group wishes to convert to its camp.”

As Osama bin Laden came to see it, repression by the American state would take the form of a U.S. occupation in the Middle East, according to the report’s analysis. “The U.S. invasion of Iraq fit Bin Laden’s updated strategy precisely. It required tens of thousands of allied ground troops who provided easy targets for guerrilla fighters, enraged Iraqi and other Muslim populations, and even led to inflammatory abuses of Muslims like those documented at Abu Ghraib prison.” Iraq was also made into a training ground for insurgents who can now apply their skills in assembling IEDs and conducting guerrilla warfare anywhere.

Why not use WMDs, then? The study argues that, first, calibrating the size of an attack is essential. “Conventional bombs and guns, targeted to harm populations the government is sworn to protect, can significantly discredit state competence and provoke delegitimizing state reactions. But weapons that significantly escalate terrorism campaigns beyond what states have become accustomed to—like the attacks on 9/11, or feared biological, chemical, or nuclear attacks—may go too far, alienating potential supporters and garnering a hardline state response that large majorities see as entirely legitimate.”

Furthermore, those who “see themselves as holy warriors on a path leading to heaven . . . seek glory in battle and . . . a martyr’s death. These operatives probably gravitate to the use of bombs and guns that give them an exhilarating sense of doing battle. Silently releasing biological and chemical agents, by comparison, may generate relatively less excitement for trigger-men.”

If all this is not comforting enough, the study goes on to detail in technical terms the practical obstacles to non-state actors acquiring the skills and equipment necessary to create and deliver radiological, biological, or chemical weapons. It’s just not that easy.

Globally, security surrounding dangerous materials has been enhanced, the report argues. Nuclear weapons can’t be manufactured by any but a handful of states, and they wouldn’t escape blame if they handed any over to terrorist groups. “Nuclear forensics” now make it possible “to trace the origin of bombs even after detonation. This effectively places a ‘return address’ on a nuclear attack.” Black-market transfers of enough highly enriched uranium or plutonium to make a bomb would be detected by passive sensors, and the material is so dangerous that ill-equipped handlers would probably be sickened or killed.

“Attempted illegal sales of nuclear material were discovered eighteen times between 1993 and 2007 as states of the former Soviet Union reacted slowly to the need to secure fissionable material,” but the amounts were minimal, totaling 17.5 pounds of uranium, whereas 50 pounds would be required for an efficient bomb.

“Dirty bombs,” which would use conventional explosives to spread radioactive material, are hardly more dangerous than the conventional bombs themselves. The materials easiest to steal—mostly used in medicine—emit forms of radiation that cannot travel through buildings or thin shields of lead, and dissipate within days. The exception is U-235, whose half-life is more than 700 million years, the report notes. But it’s hard to get.

Chemical weapons are tricky and dangerous to manufacture, dispersal is complex, and they have rarely been used. The Japanese cult Aum Shinrikyo released sarin gas in the Tokyo Metro in 1995 but killed no more than a dozen people. “Most, and the most deadly, must be dispersed at a fairly specific particle size, or ‘aerosolized,’ to reach the most vulnerable parts of the human respiratory system. Aerosolization is a difficult process that requires a technical knowledge of fluid dynamics and the coagulative properties of the material being used.” So, the study concludes, “large-scale attacks are not likely to be attempted when other means are available.”

Similarly, “biological weapons share many of the limitations of chemical weapons. They are at least as difficult to procure and prepare as the most difficult chemical weapons, and are as difficult to weaponize and disperse. Despite al-Qaeda’s multiple attempts to obtain anthrax from 1997 to 2001, they could never secure a pathogenic strain of the bacterium.” The report notes that the anthrax mailings in the U.S. were allegedly done not by a terrorist group but by an American biological weapons researcher.

Sleep well.