Success Against a Networked Enemy
WINDS OF CHANGE BLOG
by Armed Liberal at October 16, 2007 1:10 AM
I want to take a moment and talk about what may be happening in Iraq - why it is that we're seeing such a precipitous drop in attacks, how we may have gotten there, and some things to think about in terms of what comes next.
A lot of attention is (rightly) being paid to the specific tactics being employed by our military leadership, and that's obviously a key point to keep in mind. But I want to raise a slightly more subtle one, which is that there may be a structural reason for the collapse of the insurgency.
One issue we struggle with is the notion that we can't defeat a networked guerilla force (see John Robb). That truism has pretty well taken hold, and is reinforced by our perceptions of the power of networks - particularly the scale-free networks that provide good models for the Internet, for fads - and for political movements. There are many heads, and so you can't decapitate such a network, the argument goes. And since every violent act against a member of the network damages the network, and simultaneously helps it heal (by, for example, recruiting others to join the network), the issue is the ratio between damage/healing, and the attacker risks facing an impossible task, since the more damage they do the network, the stronger it may get.
The best book I know of for beginners on networks is 'Linked' by Albert-Lazlo Barabasi. He discusses his efforts to take networks apart:
Motivated by the DARPA proposal, in January 2000 we performed a series of computer experiments to test the Internet's resilience to router failures. Starting from the best available Internet map, we removed randomly selected nodes from the network. Expecting a critical point, we gradually increased the number of removed nodes, waiting for the moment when the Internet would fall to pieces. To our great astonishment the network refused to break apart. We could remove as many as 80 percent of all nodes, and the remaining 20 percent still hung together, forming a tightly interlinked cluster. This finding agreed with the increasing realization that the Internet, unlike many other human, made systems, displays a high degree of robustness against router failures. Indeed, a University of Michigan-Ann Arbor study had found that at any moment hundreds of Internet routers malfunction. Despite these frequent and unavoidable breakdowns, users rarely notice significant disruptions of Internet services.
Soon it became clear that we were not witnessing a property unique to the Internet. Computer simulations we performed on networks generated by the scale-free model indicated that a significant fraction of nodes can be randomly removed from any scale-free network without its breaking apart. The unsuspected robustness against failures is that scale-free networks display a property not shared by random networks. As the Internet, the World Wide Web, the cell, and social networks are known to be scale-free, the results indicate that their well-known resilience to errors is an inherent property of their topology - good news for the people who depend on them.
Which represents pretty much the Standard Model for our perception of fighting networked enemy forces - we kill or capture a member (a 'node' in the model), and the system routes around the damage. So it's hopeless, right?
Maybe not so much.
Because one property of scale-free networks is that they are hierarchical - some nodes (Huffington Post, Instapundit) are better-connected than others (Winds of Change) who are in turn better connected than others (The Concerned Troll). That's also a property of scale-free networks (power-law distribution). And it is apparently a property that can be exploited. Here's Barabasi:
Mimicking the actions of a cracker who brings down the Internet's largest hubs one after the other,' we embarked on a new set of experiments. Like MafiaBoy and those involved in Eligible Receiver, we no longer selected the nodes randomly but attacked the network by targeting the hubs. First, we removed the largest hub, followed by the next largest, and so on. The consequences of our attack were evident. The removal of the first hub did not break the system, because the rest of the hubs were still able to hold the network together. After the removal of several hubs, however, the effect of the disruptions was clear. Large chunks of nodes were falling off the network, becoming disconnected from the main cluster. As we pushed further, removing even more hubs, we witnessed the network's spectacular collapse. The critical point, conspicuously absent under failures, suddenly reemerged when the net¬ work was attacked. The removal of a few hubs broke the Internet into tiny, hopelessly isolated pieces.
Many people (including me) have been kind of mocking about the steady stream of 'high-value targets' that have been killed or captured in Iraq over the last year. But I've got to believe that the patient work of chasing connections and neutralizing higher and higher value 'nodes' in the insurgent network actually may be paying off as the network begins it's sudden collapse.
Indeed, our group observed an equally spectacular breakdown when we removed the highly connected proteins from the protein interaction network of the yeast cell. The same collapse was seen by ecologists when they deleted highly connected nodes from food webs. Two subsequent papers, one by Havlin's research group and another by Duncan Callaway from Cornell University, working together with Mark Newman, Steven Strogatz, and Duncan Watts, provided the analytical backing for this observation. They demonstrated that, when the largest nodes are removed, there is a critical point beyond which the network breaks apart. Therefore, the response of scale-free networks to attacks is similar to the behavior of random networks under failures. There is a crucial difference, however. We do not need to remove a large number of nodes to reach the critical point. Disable a few of the hubs and a scale-free network will fall to pieces in no time.
So it's possible to degrade and the destroy the effectiveness of networked insurgencies - and they will collapse as rapidly as they came into being.
The problem, as I'm so fond of saying, is What Next?
How do we take advantage of the opportunity opened by the collapse?
I've thought it ridiculous that people are declaring the surge a failure because a month in ther was no political reconciliation. Clearly, that is something that will lag far behind security conditions.
But it can't lag forever.
And for that, I wonder if we can't thank Joe Biden, which has provided the Iraqi poltical sphere with a common enemy. The next six months will be darn interesting.
windsofchange.net |
