Uncloaking Terrorist Networks

Modeling Terrorist Networks 

We have seen examples of networks and the application of theory to topics like traffic patterns and auctions. Though these topics are interesting and important in their own right, it isn’t always apparent how the study of networks can have a much more serious and deadly application: the study of international terrorists. In the example of high school dating:  the nodes that originally represented students now come to represent some of the most dangerous and violent terrorists in the world, the “links” that used to represent relationships between teenagers now develop into distribution networks for explosives and intelligence between terrorist plotters.

Analysts have made a graph, similar the one we saw in class representing the high school dating, showing the network of the terrorists involved in the September 11th attacks. This graph shows the network produced, including the ties that resulted from study of the interactions between those involved (especially the pilots). It shows Mohammed Atta (widely believed to be the head of the suicide hijackers) to be a very well connected node. However, further analysis has revealed interesting insight into the structure of command in terrorist networks. If weak ties (such are short phone calls and emails) are removed, Nawaf Alhazami (thought to be the hijacker-pilot of American flight 77) becomes the most powerful node. It is theorized by some that Alhazami was responsible for planning the attacks and Atta was more involved during the course of the actual attacks. In terrorist networks, properties like closeness and betweenness between nodes have very different implications. They help government agencies determine which suspects they should follow to learn more about the network, and those who are heavily involved in network traffic and whose arrest would damage the network the most.

This is one area that we have not learned about much in class, how the removal of nodes and links affects the network overall. Perhaps what makes terrorist networks so hard to stop is their resilience to the removal of nodes (arrest of suspects). These networks are designed so that the flow of information and control cannot easily be interrupted by the removal of one or two individuals. Terrorist organizations are structured as “cells”, each of which is capable of operating independently from the others and can survive on its own. These cells are often connected components in the terrorist networks, with suspects being separated by only one or two links, and having many connections to others in the cell. The lack of strong connections between cells, or to a small number of controlling individuals, makes it very hard for the authorities to dismantle these terrorists. Further study of how terrorist organizations are formed and operated will hopefully help authorities investigate and eliminate some of the most dangerous networks in existence.