At the insistence of many of my friends, I started watching Avatar: The Last Airbender (the TV series, not the dreadful film). The show appears to take place on a post-apocalyptic Earth, where humans have been divided into four tribes (fire, water, earth, and air), which can “bend” their particular element as a means of weaponization.
The world is constantly at war. The show’s narration blames this on the disappearance of the disappearance of the Avatar, the traditional peacekeeper and only person capable of wielding all four elements.
However, the lack of the Avatar fails to explain the underlying incentive for war. Today’s pre-apocalyptic world does not have an avatar, and yet most countries most of the time are not at war with most other countries. Moreover, the Avatar theory does not address war’s inefficiency puzzle, i.e. how the costs of fighting imply the existence of negotiated settlements that are mutually preferable to war. Why not reach such an agreement and end the war that has completely devastated the world economy? The Avatar might be sufficient for peace but is by no means necessary.
In contrast, I propose that the underlying cause of war is the presence of rapid, exogenous power shifts. As described in the episode The Library, the fire tribe’s ability to bend fire disappears during a solar eclipse. Likewise, the water tribe’s ability to water bend disappears during a lunar eclipse. These rare events leave their respective tribes temporarily powerless. In turn, that tribe faces a commitment problem. For example, on the eve of a solar eclipse, the fire tribe would much enjoy reaching a peaceful settlement. In fact, they would be willing to promise virtually everything to achieve a resolution, since they will certainly be destroyed if a war is fought on the solar eclipse.
But such an agreement is inherently incredible. Suppose the other tribes accepted the fire tribe’s surrender. The solar eclipse passes uneventfully. Suddenly, the fire tribe has no incentive to abide by the terms of the peace treaty. After all, their power is fully restored, and they no longer face the threat of a solar eclipse. They will therefore demand an equitable share of the world’s bargaining pie.
Now consider the incentives the other tribes face. If they fail to destroy the fire tribe during the solar eclipse, the fire tribe will demand that equitable stake. But the other tribes could destroy the fire tribe during the eclipse and steal their share. That is a tempting proposition. Indeed, the other tribes likely cannot credibly commit to not taking advantage of the fire tribe’s temporary weakness.
Finally, think one further step back, once again from the perspective of the fire tribe. If the fire tribe does not successfully destroy the other tribes before the solar eclipse, they run the risk of being destroyed on that day. From that perspective, it is perfectly understandable why the fire tribe fights.
Thus, there are commitment problems abound in the world of Avatar. The fire tribe cannot credibly commit to remaining enfeebled after the solar eclipse. The other tribes cannot credibly commit to not attack the fire nation during the eclipse. War seems perfectly rational.
Interestingly, one way out of the problem is for the fire and water tribes to agree to protect one another during their eclipses. Given that, neither side has incentive to attack during the eclipse; if that tribe did join the other tribes in an attack, then it would be left without any protection during the next eclipse. (This resembles a trual–a dual with three people.) Yet, in the series, the fire and water tribes appear to be the most bitter enemies.
One wonders if the library contained a copy of Fearon 1995 or In the Shadow of Power. In any case, you can read more about preventive war in the third chapter of The Rationality of War or watch the below video:
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William Spaniel 