Why social network analysis hasn't led us to Osama Bin Laden.

In the immediate aftermath of Saddam Hussein's capture on Dec. 13, 2003, network theory got a brief moment of glory. The Washington Post ran a story about the role of "link diagrams" in Hussein's capture, and a handful of other articles made reference to the chart that Jim Hickey and Brian Reed had constructed.

Due to the secrecy surrounding special operations, there was no mention of Eric Maddox and his colleagues, but top military commanders took note of his contribution. Within days of returning to the United States, he met with Donald Rumsfeld, George Tenet, and a host of intelligence bigwigs. He was eventually awarded the Legion of Merit award, among others, for his contributions to the capture.

Brian Reed, too, earned notice for his contribution to the hunt for Saddam. Around the time that Reed completed his dissertation on Saddam's network, he was recruited by Gen. David Petraeus (then commanding general of Fort Leavenworth) to co-author an appendix on social-network analysis for the Army's counterinsurgency manual. (He was also invited to throw out the opening pitch at a Phillies game in his native Philadelphia, which he did on July 4, 2004.) Still, social network theory has not become a central part of the training for military intelligence officers. Most of the people interviewed said that, while there is significantly more discussion of networks now than, say, a decade ago, it's still an ancillary part of the intel toolkit.

For all Hickey, Russell, Maddox, and Reed's success in Iraq, network theory is not a silver bullet. Network diagrams helped pin down Saddam Hussein after only nine months on the run. Osama Bin Laden, meanwhile, has evaded capture for more than eight years since the United States invaded Afghanistan.

The American military's challenge in chasing Bin Laden isn't directly analogous to what it faced in Iraq. For one thing, fighting an urban insurgency requires an entirely different strategy than picking through the caves of Tora Bora and the mountainous membrane between Afghanistan and Pakistan. But there may be another reason the blueprint for tracking down Saddam doesn't easily graft onto the hunt for Bin Laden: Unlike the insurgency in the early days of the Iraq war, al-Qaida is no longer a real network.

That's the opinion of Marc Sageman, a terrorism expert and former member of the CIA who served in Afghanistan for several years. Sageman, the author of   Understanding Terror Networks and   Leaderless Jihad: Terror Networks in the Twenty-First Century, argues that the still-ongoing quest for Osama Bin Laden has worked by one metric: It has effectively relegated Bin Laden to the role of a figurative leader. As the title of his second book implies, Sageman argues that al-Qaida is no longer the structured organization it was before Sept. 11. In fact, he prefers the term "blob" to "network," seeing al-Qaida and its affiliates as a loose, amorphous collection of terrorist organizations who act without central command.

Sageman is a natural skeptic who insists that counterterrorism scholarship is reliant on anecdotes rather than data. When I showed him a copy of the Saddam network, he was dismissive, saying he needed more information about how it was compiled. Under Sageman's "blob" theory, connections between players in terrorist groups evolve far too rapidly for a network diagram to keep up with. Expressing all relationships in terms of nodes and edges, he further argues, cannot account for the nuances of how people are really connected. Sageman believes social network analysis might be useful for drawing conclusions after the fact, when information about a terrorist group is more complete. He remains unconvinced of its utility as a battlefield tool.

While Sageman is one voice in a crowded field of terrorism experts, his point about the pace at which networks shift is a valid one. In Tikrit, players were captured, killed, and replaced at a low enough rate that the network was able to cohere. The churn rate is likely much higher in an extremist group like al-Qaida.

Saddam Hussein's network was also fairly rigid: The connections the dictator made throughout his decades in power were not going to disappear overnight. But unlike an insurgency based on Iraq's ancient tribal traditions, al-Qaida has the ability to shift its structure. "In its third decade, under severe pressure, [al-Qaida] has evolved into a jihadi version of an Internet-enabled direct-marketing corporation structured like Mary Kay, but with martyrdom in place of pink Cadillacs," Steve Coll wrote in TheNew Yorker in January. "Al-Qaida shifts shapes and seizes opportunities, characteristics that argue for its longevity."