Rationalist Explanations for War in the East China Sea
Image Credit: Wikimedia Commons

Rationalist Explanations for War in the East China Sea


Events in the East China Sea since 2009 have thrust to the forefront the following frightening question: will China and Japan imminently go to war? Conventional answers in the affirmative point to the deep level of historical mistrust and a certain level of “unfinished business” in East Asian international politics, stemming from the heyday of Showa Japan’s imperialism across Asia. Those on the negative often point to the astronomical economic costs that would follow from a war that pinned the world’s first and third largest economies against its second in a fight over a few measly islands, undersea hydrocarbon reserves be damned.

I can’t pretend to arbitrate between these two camps but I find that far too many observers sympathize with the second camp based on rational impulse. Of course China and Japan wouldn’t fight a war! That’d ruin their economies! I sympathize with the Clausewtizean notion of war being a continuation of politics “by other means,” and the problems caused by information asymmetries (effectively handicapping rational decision-making), but the situation over the Senkaku/Diaoyu islands can result in war even if the top leaders in Tokyo and Beijing are eminently rational.

Political scientist James D. Fearon’s path-breaking article “Rationalist Explanations for War” provides a still-relevant schema that’s wonderfully applicable to the contemporary situation between China and Japan in the East China Sea. Fearon’s paper was initially relevant because it challenged the overly simplistic rationalist’s dogma: if war is so costly, then there has to be some sort of diplomatic solution that is preferable to all parties involved — barring information asymmetries and communication deficits, such an agreement should and will be signed.

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Of course, this doesn’t correspond to reality where we know that many incredibly costly wars have been fought (from the first World War to the Iran-Iraq War). So, if wars are costly — as one over the Senkaku/Diaoyu islands is likely to be — why do they still occur? Well, the answer isn’t Japanese imperialism or because states just sometimes irrationally dislike each other (as the affirmative camp would argue). It’s more subtle.

Fearon’s “bargaining model” assumes a few dictums about state knowledge, behavior and expectations ex ante. I’ll cast the remainder of the model in terms of Japan and China since they’re our subjects of interest (and to avoid floating off into academic abstractions).

First, China and Japan both know that there is an actual probability distribution of the likely outcomes of the war. They don’t know what the actual distribution is, but they can estimate what is likely in terms of the costs and outcomes of going to war. For example, Japan can predict that it would suffer relatively low naval losses and would strengthen its administrative control of the islands; China could predict the same outcome, or it could interpret things in its favor. In essence, they acknowledge that war is predictable in its unpredictability.

Second, China and Japan want to limit risk or are neutral to risk, but definitely do not crave risk. War is fundamentally risky so this is tantamount to an acknowledgement that war is costlier than maintaining peace or negotiating an ex ante diplomatic solution.

The third assumption is a little dressed up in academic jargon: there can be no “issue indivisibility.” In plain English, this essentially means that whatever the states are fighting over (usually territory, but it could be a pot of gold) can be divided between them in an infinite number of ways on a line going from zero to one. Imagine that zero is Japan’s ideal preference (total Japanese control of the Senkakus and acknowledgement as such by China) and one is China’s ideal preference (total Chinese control of Diaoyu and acknowledgement by Japan). Fearon’s assumption requires that there exist points like 0.23 and 0.83 (and so forth) which set up some sort sharing between the warring parties. Even solutions, such as one proposed by Zheng Wang here at The Diplomat to establish a “peace zone,” could sit on this line.

If the third assumption sounds the shakiest to you that’s probably because it is. “Issue indivisibility” is a nasty problem and a subject of quite some research. It usually is at the heart of wars that seek to decide which state should control a territory such as a Holy City (the intractability of the Arab-Israeli conflict is said to be plagued by indivisible issues).

So, is the dispute over the Senkaku/Diaoyu fundamentally indivisible? Probably in the sense of splitting sovereignty over the islands, but probably not in the sense of some ex ante bargain similar to what Zheng proposed. Even if the set of solutions isn’t infinitely divisible, whatever finite solutions exist might not fall within whatever range of solutions either Japan or China is willing to tolerate — leading to war.

Fearon actually doesn’t buy the indivisibility-leading-to-war theory himself. He reasons that generally almost every issue is complex enough to be divisible to a degree acceptable by each party (undermining the infinite divisibility requirement), and that states can link issues and offer payments to offset any asymmetrical outcome. In the Senkaku/Diaoyu case, this would mean a solution could hinge upon Japan making a broader apology for its aggression against China in the 20th century or China taking a harsher stance on North Korea (both unlikely).

Relevant to the Air Defense Identification Zone is Fearon’s description of war arising between rational states due to incentives to misrepresent capabilities. China and Japan’s leaders know more about their country’s actual willingness to go to war than anyone else, and it benefits to signal strong resolve on the issue to extract more concessions in any potential deal. Japan announcing its willingness to shoot down Chinese drones earlier this year and its most recent defense plans are example of this, and China’s ADIZ is probably the archetype of such a signal. Instead of extracting a good deal, what such declarations can do is force rational hands to war over the Senkaku/Diaoyu islands.

Fearon’s final explanation — regarding commitment problems leading to war — is slightly ancillary to the core discussion about the Senkaku/Diaoyu islands given Japan’s constitutional restraints on the use of force (rendering preemptive, preventative, and offensive wars largely irrelevant in the Japanese case). Regardless, the point remains that even if the Senkaku/Diaoyu islands might seem like a terribly silly thing for the world’s second and third largest economies to go to war over, war can still be likely.

As I observe events in the East China Sea, I mostly recall Fearon’s warnings on certain types of signals leading to brinksmanship (the divisibility issue is far murkier). Both Japan and China don’t seem to be relenting on these sorts of deleterious signals. Additionally, given that Chinese and Japanese diplomats haven’t had high-level contact in fourteen months, even the more primitive rationalist’s explanation, that war occurs because a lack of communication leads to rational miscalculations, becomes plausible.

A reflection on the possible rational reasons for China and Japan to go to war over the Senkaku/Diaoyu islands highlights the seriousness of the ongoing brinksmanship in the East China Sea. If a war is fought over these long-contested islands, it will have an eminently rational explanation underlying all the historical mistrust and nationalism on the surface. War in the East China Sea is possible, despite the economic costs.

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