Researchers in Colombia, Miami, and the UK have published an article in this week’s Nature that claims to identify what amounts to universal power-law behavior (though they don’t call it that, and there are slightly different exponents for different insurgencies, but the putative universal exponent is apparently 5/2) in insurgencies. The researchers analyzed over 54000 violent events across nine insurgencies, including Iraq and Afghanistan. They find that the power-law behavior of casualties (see also here for the distribution of exponents over insurgencies) is explained by “ongoing group dynamics within the insurgent population” and that the timing of events is governed by “group decision-making about when to attack based on competition for media attention”.
Their model is not predictive in any practical sense: few things with power laws are. What it provides is a quantitative framework for understanding insurgency in general, and perhaps more importantly a path towards classifying insurgencies based on a set of quantitative characteristics. One of the nice things about universality (if this is really what is going on) is that it allows you to ignore dynamical details in a defensible way, so long as you understand the basic mechanisms at play. This insight actually derives from the renormalization group (the same one that informs Equilibrium’s architecture) and provides a way to categorize systems. So if there really is universal behavior, then the fact that the model these researchers use is just a cariacture wouldn’t matter as much as it otherwise would, and it would allow for reasonably serious quantitative analysis.
The first question about this work ought to be if similar results can be obtained with different model assumptions. The second ought to be attempting to run the same analysis on “successful” wars of national liberation to see if there are indeed distinguishing characteristics. If there are, this framework could be a valuable input to policy and strategy. When pundits talk about Iraq or Afghanistan being another Vietnam, the distinction between terrorist insurgency and guerrilla warfare is blurred. But hard data may provide clarity in the future.
Looking at the graphs you link to, only Iraq has a dynamic range of more than a decade and a half.
A -5/2 exponent is pretty steep and should be doubted without enough dynamic range.
I also doubt that “ongoing group dynamics” has anything to do with the casualty distribution. It probably tells us more about (a) distributions of crowds and (b) distributions of shrapnel in these crowds.
In an insurgency not all attacks are terrorist bombs, so that rules out that possibility. And not all armed actions are directed at civilians. Many are direct confrontations between official forces or between diverse groups.
@water tiger:
Granted that not all attacks are bombs, but perhaps it is the dominant cause (at least in Iraq, where the power law is most pronounced)? What does the raw data say?