Continuity and Change in Japanese Security Policy: Testing Theories of International Relations

Jennifer Lind
Ph.D. Candidate, Department of Political Science, MIT; and Visiting Fellow, Dickey Center for International Understanding, Dartmouth College

November 12, 2003

Traditionally, debate over Japanese security has assumed that Japan is militarily weak, and in turn asks the questions, "Why, and when might it rearm?" My project shows that Japan in fact has a strong military but shows restraint, in other words, that it has already rearmed. The question I seek to answer is then, "What explains both Japan's power and its restraint?"

Security specialists care about Japanese security for theoretical as well as pragmatic reasons. On the theoretical side, this project weighs in on the realist versus constructivist argument. Japan has been a poster child for constructivist theorists who argue that one must look at domestic issues to understand a state's behavior in the international arena. On the pragmatic side, the understanding of Japanese security affects judgments that go into defining future US policy, including perceptions of Japan in East Asia. To summarize this project, I have found that Japan is one of the world's top 3 or 4 military powers. Constructivist theories are inconsistent with the high level of military power Japan developed, as well as with the increase in Japanese military roles. Last, the project concludes that since World War II Japan has pursued a strategy of "buck-passing," consistent with offensive and defensive realism.

Realism and constructivism are paradigms, not individual theories, so neither can be falsified outright. I am testing two theories within these paradigms. The antimilitarism explanation (attributed to Thomas Berger and others) says domestic political culture and norms inhibit major changes in security policy. The case scholars make regarding Japan is that antimilitarism norms have been robust since WWII, and so they predict Japan should have a low level of military power and low level of military activity.

Realism by contrast says that the international system is the key determinant in security policy. States select a security strategy from a menu of options, where one such option is buck-passing. Under a buck-passing strategy, a state allows an ally to do the work for them. Its benefits include transferring costs of balancing efforts on to another state, and it might result in favorable conditions after a war in which two other countries wear each other out. Realism offers no clear prediction regarding Japan, but realist scholars would argue that Japan was a good candidate for buck-passing after World War II. Reasons include the existence of a powerful and credible U.S. ally, and Japan's insulation from the Soviet threat caused by geography.

Buck passers seek to maintain a balance of power. According to a buck-passing strategy, if the balance of power shifts adversely, a buck-passer will first relies on allies to restore it, though if allies fail to do this, the country would eventually increase its military capabilities and roles. Thus in order to make specific predictions for Japan, one first needs to code the balance of power in East Asia.

In coding the balance of power for the US/Japan alliance versus the USSR, I identify three periods. From 1950 to 1975, the balance of power was favorable to the US/Japan alliance. Soviet forces were concentrated in Europe. From 1975 through the 1980s, the balance of power began to favor the USSR, as the USSR built up its naval and air power. It built a large fleet and also militarized the Kurile Islands, increasing its amphibious capability against Japan. At the same time, US began to focus on the Persian Gulf, diverting naval forces from East Asia. In the post cold war period, a favorable balance of power has reemerged. Based upon this coding, a buck-passing strategy would predict Japan should develop low military power in the first period. In the middle period it predicts a need for increased military capability (in particular maritime power) as well as a call for greater military roles. These increases should taper off following the end of the cold war.

In measuring capabilities, I have chosen to look at aggregate defense spending, not defense as a percentage of GDP as many scholars do when studying Japan. I do this because the percentage indicates a level of effort - the burden of military spending assumed by society - rather than direct output, which is what really matters when analyzing a balance of power. Looking at aggregate defense spending, we see Japan overtaking other US allies in the 1980s. In the post cold war period, we see Japan as the #2 defense spender after the US as measured in market exchange rates. Adjusting to purchasing power parity, Japan falls only one slot down to #3, behind the US and Russia.

This military spending has purchased strong capabilities. In the '50s and '60s Japan's capabilities were poor, its equipment largely being left-over US equipment. Starting in the late '80s, Japan began purchasing state-of-the-art F- 15s, AWACS, Aegis cruisers, and other modern defense platforms. Its naval tonnage doubled, while the overall age of the fleet dropped significantly. It also acquired a significant fleet air defense capability with the SM-2 MR. An organic air defense capability is necessary for blue water operations, and allows the Japanese navy to sail at a distance from friendly shores, outside the range of coastal air cover. Other great powers have inferior air defense capabilities, and are accordingly limited to operations in their littoral waters. I put the Japanese navy as the world's 3rd or 4th most powerful today. In the same time period the percentage of current generation fighter aircraft in Japan's inventory rose significantly, complemented by a high number of early-warning aircraft, which are critical in utilizing fighters to control airspace. Most importantly, Japan's pilots receive a very high number of flying hours for training. I rank the Japanese air force as perhaps the 4th most powerful in the world.

Looking now at Japan's military roles, in the early period Japan refused to deploy forces beyond its shores, citing constitutional constraints. Starting in the mid-1970s, Japan took on the role of patrolling its sea lanes out to 1000 miles, and it began participating in multilateral and joint US-Japan military exercises (RIMPAC, Fleet-ex, etc.) Into the '90s, Japan can be characterized as participating in multilateral endeavors at a low but broadened level, with small military commitments to various UN and coalition operations.

In applying this data back to the two competing theories, we see that the antimilitarism theory works for the first period but cannot explain the major changes in the '80s. By contrast buck-passing also predicts low military power and involvement in 1950-75 period but also offers an explanation as to why Japan rearmed in the '80s. However a question remains as to why Japan chose a buck-passing strategy in particular from its menu of options rather than other realist strategies. Here I see a possible role for antimilitarism theory --domestic opposition to military may very well have guided policymakers in selecting a buck-passing strategy rather than a more aggressive strategy. However this project concludes that Japan's military power and participation has not been significantly constrained by domestic norms.

Jennifer Lind is a Research Fellow and Visiting Professor in the Department of Government, Dartmouth College. She is currently working on a book manuscript entitled "Sorry States: Apologies in International Politics." Ms. Lind's research interests include historical memory, East Asian security, and U.S. foreign and military policy in East Asia. She has worked as a consultant for RAND and for the Office of the Secretary, U.S. Department of Defense. Ms. Lind holds a Master's degree from the School of International Relations & Pacific Studies at the University of California San Diego, and a B.A. from UC Berkeley. She is receiving her Ph.D. from MIT's Department of Political Science this year.

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