A Study of Japan-US Asymmetric Alliance Relations in the Perspective of Hub-and-spoke System in East Asia

Abstract As an important part of the US Indo-Pacific strategy, East Asia has become the frontline for containing the Soviet Union and China. For historical reasons, the US has not succeeded in building a NATO-like defense system in this region, choosing instead to build a "hub-and-spoke system" with the US at its core, of which the Japan-US alliance is one of the main pillars. This paper aims to analyze the asymmetrical relationship between Japan and the US through the current military and economic interactions between the two sides, considering the current situation in terms of economic and trade exchanges, economic aid, US forces in Japan, and military cooperation, to understand Japan's position and role in the US strategic layout in East Asia and to predict the future direction of the Japan-US alliance.

Keywords Japan-US alliance, Dependency, Asymmetrical alliance, Japanese diplomacy

I. Historical Background of the Japan-U.S. Alliance

Since Japan's return to the international community after WWⅡ, the Japan-U.S. alliance has gone through about 70 years, counting from the signing of the Treaty of Mutual Cooperation and Security Between the United States and Japan in 1951, and even since the entry into force of the new security treaty, the alliance has gone through about 60 years, Japan and the U.S. have developed extensive and profound cooperation in national strategies, which have deep historical roots and realistic foundations. In the new treaty, which was re-signed in 1960, it was made clear that the two sides would undertake their treaty obligations and jointly defend Japan, while the U.S. could use Japanese military bases for the duration recognized by both countries.

Japan had just walked away from the post-war period, and although Japan made peace with various countries under the coordination of the United States, its neighbors were still suspicious of Japan, additionally, Japan's lack of military capability under the constraints of the Peaceful Constitution made an alliance with the United States undoubtedly the only option. The United States, on the other hand, needed to form an encirclement in East Asia out of the need to contain communist expansion, and Japan's geographical location and national strength proved to be an indispensable link that also needed to be pulled together in the form of an alliance. But this tolerant policy aroused the misgivings of other U.S. allies, the Australian and New Zealand governments bluntly pointed out that the people of Australia and New Zealand could hardly agree to conclude a security treaty with Japan, and that the collective defense of the Pacific should be presided over by Australia, New Zealand, and the United States, so the Pacific defense system, similar to the multilateral mutual aid system of the NATO model that Dulles pushed for, had to be sunk in stone. Instead, the U.S. has opted for a collective defense system with the U.S. as the core, a forward presence as the cornerstone, and bilateral alliances with each country, supplemented by multilateral security mechanisms, which is also known as the “hub-and-spoke System”. According to Victor Dong Cha, a Korean American scholar, the close bilateral relationship between Japan and the United States formed the cornerstone of the U.S. informal empire in Asia and served as a template for the form of U.S. alliances with other allies in the region, and the tight bilateralism represented by the hub-and-spoke systemsuccessfully institutionalized the Japan-U.S. alliance and shaped Japan's position in East Asia today. Japan's position in East Asia today.

After the end of the Cold War, the alliance between Japan and the United States did not dissolve with the collapse of the Soviet Union. Taiwan Strait Crisis and Korean nuclear issue made the two countries realize that the security situation in East Asia had not fundamentally changed and that there was still a need to maintain the alliance, and the United States needed a channel to intervene in East Asian affairs. For Japan, security concerns and a stagnant Japanese economy mean that the benefits of maintaining the Japan-U.S. alliance will outweigh the costs, allowing it to better respond to threats from the neighborhood and improve relations with South Korea, Taiwan, and other countries under U.S. coordination. Based on this, the cooperative relationship between the Japan-U.S. alliance has increased rather than decreased, and bilateral relations have entered a new phase.

Today, Japan no longer limits its vision to its security and bilateral relations between Japan and the U.S. In Diplomatic Bluebook 2022, Japan characterizes the Japan-U.S. alliance as the foundation for peace, security, and prosperity for the entire Indo-Pacific region including Japan, and the importance of the Japan-U.S. alliance will continue to rise as the form of regional security becomes more severe. In fact, with the increasing complexity of international relations and geopolitics, Japan has become increasingly aware of the importance of the United States in its national strategy due to the intensification of non-traditional security issues and territorial disputes between China and Japan, Japan and South Korea, and Japan and Russia, and has actively made overtures to the United States to enhance its international status and defense capabilities. Considering that Japan's stand can directly affect the balance of competition between China and the U.S., the U.S. side is also happy to form an encirclement around China for its Indo-Pacific strategy. Today, Japan is actively advocating the CPTPP and the QUAD mechanism, and promoting the Free and the FOIP, showing that it is not willing to just follow the US, but wants to show its independent diplomatic capability in the international arena.

Given the differences between Japan and the United States in terms of comprehensive national power, the alliance between the two countries is not based on equality and symmetry, a feature that directly determines the positioning and actions of the two countries in the alliance. Therefore, this paper hopes to analyze the real structure of the Japan-U.S. alliance, especially the extent of Japan's dependence on the U.S., through current studies on asymmetrical relations in international relations to provide a clearer understanding of the Japan-U.S. alliance and help China better respond to challenges from its neighborhood.

II. Prior Study of the Japan-U.S. Alliance

The Japan-U.S. alliance is literally an alliance formed based on the security system. Through the Treaty of Mutual Cooperation and Security Between the United States and Japan, the two countries are deeply bound in various fields such as politics, economy, and defense, but the two countries present non-equality, non-symmetry and non-reciprocity, and for historical reasons, the influence of the U.S. on Japan covers various aspects such as economy, society and politics. Neorealists do not deny the existence of hierarchy in international community, and they explain it from internal, external, and game perspectives. David A. Lake argues that international authority stems from the recognition of the international order provided by the dominant state by the subordinate state. Patricia A. Weitsman, on the other hand, introduced theories related to alliances in her work, and Randall L. Schweller proposed the balance-of-interest theory based on a critique of Kenneth Waltz, who argued that states form alliances out of interest rather than security.

Regarding the study of the Japan-U.S. alliance, in addition to Yue Shengsong and Victor Dong Cha above, who compare the similarities and differences between the hub-and-spoke system and the pan-ripple relationship in their article, Meng Xiaoxu and Wang Shan point out that the expansion of the new Security Bill has given the U.S.-Japan alliance a global operational capability, and Xu Gangyan suggests that the alliance has developed into a military alliance with global attributes. Through studying of the alliance, Bao Xiaqin and Cui Yingzi point out that Japan is playing an increasingly important sub-axis role, and that the hub-and-spoke system is transforming into a web-like structure driven by Japan and the United States. Japanese scholar Jyo Sako and Korean scholar Jiyun Kih both argue that the Japan-U.S. alliance has been incorporated into Japan's role to contain China and to promote part of its liberal and open Indo-Pacific strategy, and that Japan will play a greater self-help role in East Asia as the United States declines. At the same time, however, many scholars have added the hidden concerns of the Japan-U.S. alliance, such as Jiang Haiyun, who points out that Japan's unilateral pursuit of reciprocal relations and the game of interests between the U.S. and Japan both constitute destabilizing factors for the alliance, as well as the fact that with the rise of China, failure to properly handle the trilateral relationship between China, the U.S. and Japan will directly affect the situation in East Asia.

Some scholars have also devoted themselves to the Japan-US relationship from the perspective of dependence, such as Pro. McCormack, who argues in his book that the core of the US-Japan relationship is a deep-rooted subordination structure, and that Japan can only unilaterally follow the demands of the US and become a "subordinate state". Wolferen, on the other hand, argues that Japan is a "protected state" of the United States, and that it has not lost its independent statehood while being highly dependent on the United States. Xiang Haoyu proposes four dimensions to measure Japan's dependence on the U.S., including value recognition, political rewards, economic interests, and security guarantees.

Although there have been a lot of studies on the Japan-U.S. alliance and asymmetric alliance theory at home and abroad, unfortunately, apart from these academic macro-analyses and studies on bilateral relations between Japan and the U.S., there is still a lack of research on the role of the Japan-U.S. alliance under the overall U.S. East Asia strategy, and the empirical studies on the Japan-U.S. alliance also need to be supplemented, and this paper intends to fill this gap from an empirical perspective.

III. Research Methodology

This paper focuses on the analysis of the political game between the two sides from a contemporary perspective, considering the international context in which the Japan-US alliance was shaped. At the same time, based on a realist empirical analysis, and considering the existing literature, it conducts a brief analysis of the Japan-US hierarchy in two dimensions: the military dimension —— the US military forces stationed in Japan, the number of independent Japanese military alliances and military cooperation, etc. and the economic dimension —— the extent of Japan-US trade and economic assistance, etc. A brief analysis of the relationship, the greater the military and economic dependence, the more significant the Japan-US alliance hierarchy and asymmetry.

In view of the limited materials used and the author's standard, as well as the fact that the dimensions of the alliance relationship are relatively homogeneous, there are inevitably biases and it is difficult to fully understand the realities of the Japan-US alliance.

IV. Analysis of Japan's military asymmetry towards the United States

Japan is surrounded by sea on all sides, and is a typical island country, geographically separated from the Korean Peninsula by sea. For historical reasons, most of its East Asian neighbors have long-standing grudges against Japan. In addition, China, South Korea, and Russia, with which Japan has territorial disputes, are all regional powers, and Japan has doubts about its national security. As an important part of the US military strategy in the Western Pacific, the Japan-US relationship has always been part of the US strategy to contain China as part of the First Island Chain and South Asian security. In recent years, as the US strategic focus continues to shift towards the Indo-Pacific region, Japan-US military relations have grown closer and cooperation has deepened, and the alliance between Japan and the US has continued unabated. At the US-Japan summit on 23 May, the two sides issued a joint statement in which the US side pledged to improve the alliance's defense capabilities across the board and provide all support, including nuclear capabilities, while clearly stating that the Diaoyu Islands are covered by the security treaty; Kishida also said he would fundamentally improve Japan's defense forces across the board and increase military spending.

Although the US-Japan alliance has undergone brief shocks during the Trump era in the past few years, the relationship has not been fundamentally damaged, and both joint military exercises and military trade between the US and Japan have been maintained at a high level. Since the Korean War, the US has pushed Japan to rearm and encouraged it to buy US weapons, and as Japan became a major economic power, it quickly became one of the main US military markets in Asia. Obviously, Japan is quite used to foreign policy swings caused by the instability of the US domestic situation, as the legislative and executive branches in Washington have always changed hands between Republicans and Democrats, and historically, Japan has experienced events including the Nixon shock, the signing of the Plaza Accord and the US withdrawal from the Kyoto Protocol, so it is not very concerned about the volatility of US-Japanese relations brought about by Trump.

However, it is also due to Japan's high level of economic development and its military-industrial system's ability to circulate on its own that the US has not given Japan too much military aid, compared to the National Defense Authorization Act 2023 signed by the Biden administration on December 23, which states that it will provide Taiwan with US$10 billion in military aid and US$2 billion in military loans over the next five years. As the world's third largest economy and a manufacturing powerhouse, Japan can afford the costs of the alliance and is deeply involved with the US in the military industry, which has allowed the US to value Japan's role.

Of course, in addition to the security treaty, Japan and the US also established CJOEP for unified command in emergency situations, and on this basis established the Joint Plan Group for Air, Land and Sea Defence. During Abe's second term in office, the Japanese government promulgated the National Security Strategy and the Defence Plan Outline under the principle of "active pacifism", which lifted restrictions on arms exports, expanded Japan's military forces, and lifted the ban on collective self-defence, making it possible for Japan to cooperate with other countries. This has opened the possibility of military cooperation between Japan and other countries. In addition, based on the 2015 revision of the US-Japan Defence Cooperation Guidelines, the US and Japan have established a multi-functional, multi-level coordination mechanism, including but not limited to the Security Coordination Committee and the Cooperation Planning Workshop, to ensure unified training and wartime military dispatch. Since then, in the context of the Indo-Pacific Strategy, Japan has frequently participated in military exercises with other countries, such as the Malabar military exercise in 2015, the joint training of the US, Japan and South Korean air forces in 2017, and the maritime training of six countries, including the US, Japan, South Korea and Australia in 2018, with 20 other countries participating as observers. As the Indo-Pacific strategy continues to be promoted and the Chinese navy becomes stronger, the number of multilateral military exercises in the region centered on the US-Japan alliance will continue to increase.

According to DMDC, as of June 30, 2022, there will be 35,688 U.S. troops in Japan, including 18,676 Marines and 12,640 Air Force personnel, the highest number in East Asia. By contrast, the number of troops stationed in South Korea is only 26,416, mainly land forces, while the number of troops stationed in Australia, New Zealand and the Philippines is far less than in Japan and South Korea. It is worth noting that the creation of the Axis spoke system itself was the result of the reluctance of East Asian allies to work with Japan. In other words, it can be said that the US formed the present East Asian alliance in order to bring Japan into the alliance system and bring Japan back into the modern international community to realize the Pacific security plan.

At present, Japan faces four main security problems: firstly, the intensification of the modernization of the military forces of its neighbors and their frequent military activities, especially the several missile tests by North Korea in recent years have aroused strong concern in Japan; secondly, the growth of China's economic power and the relative stagnation of Japan's economy have made Japan feel the pressure from China more and more; thirdly, the further frequency and expansion of Russia's military activities; and fourthly, Japan's relationship with China, South Korea and Russia; Fourth, Japan's territorial disputes with China, South Korea and Russia may cause turbulence in regional relations. Faced with the above problems, Japan has not relied solely on the United States. As one of the non-NATO allies of the United States, Japan has no other clear military ally in its diplomacy, but it has not stopped working closely with its US allies such as Australia, the Philippines, and South Korea. For example, Japan has not only repeatedly conducted cooperative military exercises with Australia and the Philippines, but also expressed its intention to strengthen security cooperation and expand joint exercises between Japan and the Philippines at the "2+2" meeting of foreign ministers and defense ministers, as well as multilateral security cooperation between Japan, South Korea, Australia and India. At the same time, Japan has not relaxed its engagement with China and Russia, and even during the Abe, Kan and Kishida administrations, certain channels of dialogue have been maintained between China and Japan, and when tensions arise, Japan is interested in cooling them down to avoid military friction between China and Japan. However, Japan will not relax its ties with the US-Japan alliance and may even strengthen them because East Asia structurally lacks a multilateral security mechanism at the governmental level, and if Japan were to take more independent military action it might cause scorn among its neighbours, whereas joint action with the US would avoid the concerns of others, but what Japan needs to worry about most is the level of protection the US can give in the event of a possible low-intensity confrontation, and this will be a factor in Japan's unease with the Japan-US alliance.

In summary, I believe that Japan's military dependence on the US is a highly asymmetrical relationship.

V. Analysis of Japan's economic asymmetry towards the US

Regarding the economic asymmetry between strong and weak countries, two scholars, Shiping Tang and Joey S.R. Long, proposed that the multiplier of total GDP and GDP per capita can be used to represent a country's strength, where the former variable refers to comprehensive strength and the latter variable refers to technological superiority, while the can be used to calculate the difference in strength between the two countries. The larger this value is, the greater the relative strength of the United States, the greater the economic asymmetry between the two countries. The World Bank database shows that in 2021 Japan's GDP will be US$4.94 trillion and its GDP per capita will be US$39,312.7, while that of the United States will be US$23 trillion and its GDP per capita will be US$69,287.5, which is 4.6 times that of Japan and 1.8 times that of Japan. We can calculate that the difference in power between Japan and the US is about 0.91. Although the US has a certain advantage over Japan in terms of individual variables, this advantage is not overwhelming in terms of the combined results, even from a purely economic point of view, the role Japan plays in global and regional affairs cannot be underestimated, and this also means that as a major economic power Japan has considerable This also means that as a major economic power Japan has considerable potential for war.

The Japan statistical yearbook over the years show that China is still Japan's primary trading partner and the object of its imports and exports, while the United States comes second and other countries in East Asia occupy a far smaller share than China and the United States. Therefore, for some time to come, economic factors will continue to play a more stable role as ballast between China, the United States and Japan, but this cannot simply mean that Japan is more economically dependent on China. As a developed country in Asia, Japan has always been a world leader in its traditional industries, and because of its lack of resources, it has been an export-oriented country in the industrial chain, importing upstream components and exporting finished products. For a long time, Japan played the role of the "head of the goose" in the "goose formation model". Typically, Japan purchases upstream materials from regions such as Russia and China and exports products to Europe and the US, in the sense that Japan's industrial structure is more compatible with that of the US than competitive with that of China. As a result, although the US does not have the same share of total imports and exports as China, it also maintains a perennial share of over 10% of Japan's foreign trade, and Japan attaches great importance to its economic and trade relations with the US.

Of course, the long-term existence of the Japan-US alliance is to some extent a result of the growing imbalance in economic relations. Since 1960, Japan has been responsible for the lease of US bases in Japan, the welfare and labor costs of Japanese employees on the bases, and has borne the highest expenses of any US ally. The US, on the other hand, has given Japan a correspondingly lenient policy on issues such as market access, resulting in a large trade surplus for Japan. However, we cannot ignore the economic differences between Japan and the US. The two sides have had a long-standing dispute over tariffs on agricultural products and the automobile industry, and there were several rounds of negotiations on this issue, and ultimately Japan's concessions in the Japan-US Trade Agreement did not exceed the limits of the CPTPP.

At the same time, Japan's economic strength has allowed it to be more comfortable in economic diplomacy, so it is actively participating in regional economic cooperation, including the CPTPP, EPA and RCEP, as well as aligning its domestic development plans with the Belt and Road Initiative to achieve sustainable economic growth. Under the influence of Trump's trade protectionism, Japan is engaged in comprehensive economic diplomacy, regional economic integration, deepening economic cooperation between China, Japan and South Korea, and energy diplomacy in the Middle East to ease the economic and trade pressure caused by the US. In addition, Japan is also providing ODA aid to other countries, and this has become one of the factors that have improved Japan's international image.

In summary, I believe that Japan's economic asymmetry towards the US is moderately weak.

VI. Conclusion

Since Japan's return to the international community after the war, Japan-US relations have taken on a special character compared to those between the US and its other East Asian allies. Based on the studies above, we can clearly identify the asymmetry between the Japan-US alliance and the fact that the US enjoys a certain authoritative voice over Japan in the regional order, that Japan has always followed the US in diplomacy and that, whether for historical, geopolitical or ideological reasons Both countries will continue to strengthen the existing alliance in the short term. Although Japan's military dependence on the US is significant in the military dimension, it is not entirely dependent on the US in the economic dimension, and the Japanese government is consciously promoting the diversification of its economy to break out of this dilemma in order to gain more leverage in the Japan-US game. Based on this, I believe that the Japan-US alliance is not entirely asymmetrical.

This conclusion is favorable to China. According to Glenn H. Snyder's theory, there is always a pull between allies in the form of "abandonment" and "implication", but in a bipolar situation, the risk of being abandoned is much lower than the risk of being implicated, which makes the differences between allies persistent but not seriously threatening. Japan would not want to be implicated in a confrontation between the US and China, and the same goes for the US. The strengthening of the Japan-US alliance is an important means for the US to contain China and a channel for US involvement in East Asian affairs. From a macro-strategic perspective, the strengthening of the Japan-US alliance will allow the US to position itself at both ends of the Eurasian continent to contain China and Russia. An obvious example is the US attitude towards the Sino-Japanese territorial dispute: on the issue of the Diaoyu Islands, in a phone call with Biden on his first day in office, Biden said that the US would protect Japan's security on all fronts, including the Diaoyu Islands, in accordance with the US-Japanese Security Treaty, which is in effect an endorsement of Japan's sovereignty over the islands. But like most countries, direct military conflict between the US and China would be detrimental to Japan, while maintaining the US-China rivalry would be more profitable for Japan, which is relying on US military protection while taking advantage of China's economic growth, so while the US-Japan alliance will be further strengthened and Sino-Japanese tensions will persist, the Japanese authorities are doing their best to avoid a direct military flare-up.

We need to recognize that the maintenance of an alliance depends on the member states' weighing of security benefits and costs, and that while the US is giving Japan greater strategic autonomy, it is also pushing itself to invest more strategic resources, and that once the US is in a strategic contractionary posture and fails to deliver on its security commitments to Japan, the Japan-US alliance will rapidly disintegrate. Some scholars have pointed out that the next 10 to 20 years will be uncertain and potentially dangerous for Japan because of the rise of trade protectionism and extreme populism in the US, which the US media has called "the eve of Pearl Harbor", and it is clear that internal problems in the US will weaken US national strength and international engagement, and may also lead to more aggressive actions against It is also possible that more aggressive measures could be taken against other countries, undermining the international order established by the US. However, Japan remains convinced that the Japan-US alliance remains the most important, if not the best, option for Japan's security strategy, even if the reliability of the alliance is in question.

With the decline of the United States and the rise of China, Japan will gain greater autonomy and become more dependent on Washington for national security and global diplomacy. These changes are impacting the current East Asian order, sending it into an unstable "drift" and allowing the Japanese right-wing to seek constitutional amendments and the lifting of the ban on collective self-defense. China should take advantage of the Japan-US alliance, maintain its strategic stability, use its economic advantages and multilateralist platform to properly deal with Sino-Japanese conflicts and territorial disputes, and maximize the strategic pressure from its neighboring countries in order to guarantee the stable environment needed for its peaceful rise.