In particular, with President Obama's announcement this month that 30,000 more U.S. troops were headed to Afghanistan, on top of 68,000 already there, some scientists are asking the question: Is that enough? The question has been debated by political and military planners, but researchers are now examining it through the lens of science.
"There is a danger that if we do not increase the numbers by enough, this strategic decision will actually increase the duration of the conflict," says physicist and political theorist Sean Gourley of the University of Miami (Fla.), an author of a study in the current issue of the journal Nature. The study, led by Colombia's Juan Camilo Bohorquez of the Universidad de Los Andes in Bogotá, finds that "the sizes and timing of violent events within different insurgent conflicts exhibit remarkable similarities," and he posits "a unified model of human insurgency."
How do they do that? In the study, the researchers examined 54,679 attacks in nine insurgencies, rebellious wars typically fought with terrorism and subversion, from 1969 to 2008. The conflicts took place in Afghanistan, Iraq, Senegal, Colombia, Sierra Leone, Israel and the Palestinian Territories, Peru and Northern Ireland. The researchers compared the timing and frequency of attacks for mathematical patterns, looking to see whether they took place differently in different wars.
Instead, the probability of daily insurgent attacks followed the same pattern, an exponentially growing curve with its steepness determined by the size of the insurgent-sympathetic population. Rather than attacks occurring randomly, the study says, insurgents worldwide developed a pattern: committing bombings or attacks on quiet days, then waiting for news of the event and then planning for the next attack, bearing in mind past attacks by other groups. Rather than groups directly collaborating with one another, each attack signals other groups, in a manner Gourley compares to competing groups of financial traders reading purchases by others in the global marketplace as signs on whether to buy or sell. Taliban members, in the model, ambush convoys mostly to gather video of burning trucks to show off to competing groups over the Internet.
Nodding to social scientists such as John Robb, author of last year's Brave New War: The Next Stages of Terrorism and the End of Globalization, the study authors say a "soup of groups," rather than any hierarchy, dominates insurgencies. That dooms efforts to bump off minor leaders of insurgencies, Gourley says, as the next-strongest group just bubbles to the top of the soup.
In November, French media officials told cable provider Eutelsat to stop carrying the TV network run by Hamas, a group listed as a Palestinian terrorist organization by the U.S. State Department. But "the addition of media into a conflict does not change the total amount of violence; the media simply provides a global signal that changes the way violence is distributed within the ecosystem," Gourley says. "What is interesting, though ... is that even unbiased 'just report what happened' journalism has a significant impact on the way violence is distributed."
So, what to do? In Afghanistan, the results suggests that NATO needs a 15-to-1 troop advantage over insurgents to break the curve of increasing attack probabilities. The Army Times reported in October that about 25,000 Taliban troops are thought to be in Afghanistan, facing a 12-to-1 imbalance against the 300,000 international and Afghanistan security forces. An additional 30,000 U.S. troops pushes the imbalance to about 13-to-1.
A skeptical view
"I'm underwhelmed. Seems like an awful lot of number-crunching for a meager output," says former CIA counterterrorism analysis chief Paul Pillar of Georgetown University in Washington, D.C.
"The chief output is the finding that violent incidents in insurgencies tend to come in bunches rather than reflecting a random distribution," he said by e-mail. "I don't see how that points to any one model of the internal shape
of insurgencies, or how it constitutes a challenge to models that posit hierarchies or networks (guiding insurgencies). Frankly, I don't see how this approach would be of use to counterinsurgency planners or policymakers."
But Gourley says the real advantage is that the model allows planners to test all kinds of strategies in a computer, rather than real life, from shutting down cellphones to squashing particular groups. "This is important, as it is cheap to do and there are no lives put at risk by running the experiments," Gourley says. With the war in Afghanistan expanding, he argues, another angle on insurgency can't hurt.