Detail from Picasso's "Guernica" - 1937
With the end of 2018, also the centennial of the end of the Great War (or WWI) is over. It passed remarkably in silence: a few celebrations, but little or no discussion of the reasons and the consequences of that war, supposed to be the one that would "end all wars." Of course, it was too much to expect that wars would ever end, but maybe we could have at least learned something from rethinking to a conflict that caused some 40 million victims for no evident purpose. But that didn't happen (if you can read Italian, you may be interested in a reflection of mine on the subject).
So, the world situation, today, looks more and more similar to the military build-up that took place in Europe in the years preceding the Great War. The Great Powers are arranging their forces as if they were setting their pieces on a giant chessboard. At some moment, someone may well decide to make the first move. And, in this giant chess game, the kings can wipe out all the pieces on the chessboard in a single move with their nuclear warheads.
It would be nice to follow Steven Pinker's optimism about modern times, supposed to have become less violent. There may be such a trend for the past few decades, but it is always dangerous to extrapolate from a limited dataset. In this case, the optimism of Pinker seems to be simply wrong if measured over a time span of several centuries. This is the result of an analysis of the data for the conflicts of the past 600 years that myself and my coworkers Martelloni and Di Patti performed in 2018 -- it was thought, in part, as a way to celebrate the centennial of the Great War.
Our results are mostly a confirmation of a series of analyses that was started by Lewis Fry Richardson, pacifist and polymath, who was the first to study wars trying to understand their statistical patterns. It is a field that today has grown and arrived at a number of conclusions, mainly that war is a statistical phenomenon largely independent from religions, ideologies, money, and great leaders. It is an "emergent phenomenon" of the complex network of interactions among human societies worldwide. There is some evidence that wars are becoming less frequent, but they are also becoming more deadly. There follows there is a chance of a major conflict in a non-remote future that could dwarf all past conflicts in terms of the destruction it could cause. On this point, see a recent paper by Aaron Clauset.
Unfortunately, the results of these studies are practically unknown beyond the small group of practitioners engaged in it and with every new war we repeat the mistakes of the Great War, thinking that a war could be a way to end wars -- it is something that was repeated as recently as with the 2003 invasion of Iraq. As usual, we are marching blindfolded into the future and the future may not be kind to those who don't understand it.
I have already reported some preliminary results of this study (also here, here, and here). Now you can read our complete paper on ArXiv, and here are some excerpts.
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Pattern Analysis of World Conflicts over the past 600 years
We analyze the largest database available for violent conflicts, the one prepared by Brecke (Brecke 2011), covering some 600 years of human history. After normalizing the data for the global human population, we find that the number of casualties tends to follow a power law over the whole data series for the period considered, with no evidence of periodicity. We also observe that the number of conflicts, again normalized for the human population, show a decreasing trend as a function of time. Our results tend to support the idea that war is a statistical phenomenon related to the network structure of the human society.
Our contribution in this field consists in validating the Brecke conflict database (Brecke 2011), among the longest and most complete ones available. This analysis confirms previous work, see e.g. (Clauset 2018) , (Clauset and Gleditsch 2018) for a general discussion. The data indicate that power laws are common in the distribution of violent conflicts in human history – in this case, the trend is clear when the number of casualties is normalized for the increasing world population. Note also that the normalized number of conflicts per year tend to decrease with time – this result indicates that in modern times war have tended to become less frequent, but more destructive. In practice, these results confirm that there is little evidence supporting the idea popularized by Pinker (Pinker 2011) that humankind is progressing toward a more peaceful world. A new major conflict might be possible in a non-remote future, as discussed among others by Clauset (Clauset 2018). These results seem to indicate that human conflicts are a critical phenomenon: we could say that humans worldwide tend to form societies existing in a self-organized critical condition, as defined by Bak et al. (Per Bak, Tang, and Wiesenfeld 1988). In these conditions, war is simply one of the methods that the system has to dissipate entropy at the fastest possible speed (Kleidon, Malhi, and Cox 2010),(Trinn 2018). In other words, war appears to be an unavoidable consequence of the behavior of human beings, and perhaps of other primate species (de Waal 2000).
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