The US Cannot Take the Japanese Alliance for Granted

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When discussing the opportunities and challenges of foreign policy in East Asia, most Americans immediately assume that China is the primary subject. Certainly, China is essential to the calculus of geopolitics in East Asia and elsewhere. However, it is far from the sole driving force in the region. Japan is likely to be the ultimate determining factor in the peaceability of East Asia. As the world’s fourth largest economy, it is too big a player to ignore. Despite its abdication of military power, Japan retains—indeed exudes—the technological capacity to be a great power. It lacks only the popular political will to assert hard power. Such apprehension is unique to Japan’s distinct, but increasingly distant, history. As China grows, Japan’s abrogation of force is not likely to hold. This is especially true as the US is forced to confront the limits of its influence and power in East Asia. As US economic relations with China increasingly conflict with US security commitments to traditional regional allies, Washington will be forced to prioritize one over the other. Prioritizing Sino-US trade may well indeed be the smarter long-term play for the US, yet it will come at the expense of Japan’s confidence in US security commitments. Such a deviation will fundamentally undermine the existing US led world order in a critical region leading to greater instability as states like Japan seek new arrangements to ensure their security. Managing this challenge is the principle task of US policy in East Asia if it is to maintain stability.

Japan’s Underlying Strength

Japan is a great power, but it shuns its full potential. In 2017, Japan had a GDP of $4.8 trillion making it the fourth largest economy in the world (CIA, 2019). It is a hot bed of cutting-edge technological development including civilian nuclear power (Holroyd, 2017). It has an enduring culture with an established government and a demonstrated ability to cope with manmade and natural disasters (Kissinger, 2015, p. 181). Yet, for all these advantages, Japan remains distinct among great powers in that it voluntarily eschews military force.

The Japanese Self Defense Force (JSDF) are constrained by Article 9 of the Japanese Constitution renouncing war and any formal military forces (The Constitution of Japan, 1947). JSDF deployments are in concert with UN or other peacekeeping operations with a notable exception being the JSDF’s participation in Iraqi Freedom (Watts, 2003). Prime Minister Shinzo Abe continues to fight for changing the constitution. Doing so would allow Japan to participate in collective self-defense with its allies (The Economist, 2017).

As Japan’s most important ally, the US supports Prime Minister Abe’s efforts to reinterpret the constitution (Smith, 2014). From the US perspective, Japan could operate more like Germany: a strong economic ally with advanced military capacity that bolsters US power in the region with minimal efforts by the US. Under the existing language of Article 9, Japan is likely to fall in to the same category as Israel: an ally with great latent power that is unable to project or fully utilize that strength in its home region. The US military becomes the primary guarantor of security in such a region. In East Asia, this dynamic has benefited Japan by allowing Tokyo to pursue vigorous economic development without the historically concomitant martial build up. Never-the-less, the extent of Japan’s economic power, and it’s latent—but underutilized military capacity—means Japan meets three of Flemes’ requirements for great powers (Flemes, 2007, p. 8).

Japan’s Geopolitical Situation

Japan sits in a geographically precarious position. As an island nation it must import nearly all the raw materials necessary for a modern economy—a task whose difficulty has only increased as Japan’s economy advanced during the second half of the 20th century. This trade requirement means Japan is fundamentally in need of a beneficial relationship with a continental power. Russia, China, and South Korea make the most logical sense. Russia has vast natural resources and would likely leap at the chance for increased trade with a major industrialized economy. Yet, Russia and the US are at odds over many issues and Japan is unlikely to jeopardize its relationship with the US. China is the world’s second largest economy with vast natural resources and South Korea is a fellow US ally. However, Japan has a long and often fraught history with both states. Japanese war crimes during WWII are only the most recent transgressions in relationships that go back centuries. Such cultural dynamics create inherent tension that can rapidly escalate minor events. The tit for tat response over contested islands in the Senkaku’s illustrates this point well.

How a Rising China Could Impact Japan

China’s sheer size along with it’s economic and (growing) military clout in the region undermine Japan’s position. As a trading partner, Japan has been displaced as the largest economy in the region. Now, China is able to offer access to far larger domestic markets as well as massive aid and infrastructure packages bilaterally through the Belt and Road initiative as well as through multilateral development banks (Stuenkel, 2015, pp. 127-8). Southeast Asian states in particular are susceptible to Chinese bullying tactics. Japan has attempted to counter this through a selective application of high-end development aid in the region (Kobara, 2018; Qi, 2018). Doing so provides a subtle alternative to China and demonstrates Japan’s practical value as a partner. This is especially useful in Southeast Asia and with states like India and Australia. Each have economic and geographic relationships with China they cannot avoid, but do not want to be dependent on.

Yet China’s rise cannot be papered over or ignored. Arguably the most important bilateral relationship in the world is that between the US and China. The scale of their trade is immense, totalling over $700 billion for imports and exports in 2017 (Observatory of Economic Complexity, 2018). In the coming decades, the relative and literal value of that relationship will almost certainly increase. For the US this is a beneficial outcome, but it will present Washington with hard choices that have significant impact on regional security. Japan and other powers on the Chinese periphery (including the US) will be increasingly pressured to acquiesce to Beijing’s conception of order or face economic costs.

If the US prioritizes a strong economic relationship with China, the US will have to acknowledge limits on its own power and the actions it can take. In general, US retrenchment does not automatically mean that China will be the direct or sole beneficiary. However, because the US will have to circumscribe its actions in a region where China is the dominant player, at the expense of states who are caught between the reality of Chinese power and history of US alliances, China will be best positioned to benefit with the least amount of effort.

Taiwan serves as a good example of this. One of the shibboleths of US policy in East Asia is that Taiwan must remain free.   Since 1949 when Chaing Kai Shek and his Nationalist Army fled the mainland for the island province, the US has guaranteed Taiwan’s nominal independence from China (Bush, 2019). Beijing has never subscribed to this, yet has recognized the practical power dynamics and been willing to make policy choices on a much longer timeline than the US. Chinese influence in Taiwan will likely expand as cross-strait trade grows. Equally important, China’s military development over the last 30 years has had the dual effect of challenging US dominance in the region and enabling more efficient cross strait operations (DIA, 2019, pp. 7-11).

However, since the end of the Cold War, the symbolic power of a “free China” vs. a “Red China” has waned in the popular US perception. Mainland China, while certainly not free, has been destigmatized as US businesses came to rely on its vast labor pool, natural resources, and now markets. Consequently, the idea that Taiwan must unequivocally remain independent does not hold quite as tightly as it used to (Parameswaran, 2018). Added to this is the fact that China does not need the US to reverse position on Taiwan. Merely preventing the US from hindering China’s dominance of Taiwan will suffice. By leveraging its economic relationship with the US, and creating a face-saving political option, China could ultimately break the US security guarantee to Taiwan. Such a break would sound alarms at the highest levels in Tokyo.

Another similar, and likely more dangerous, possibility is China breaking South Korea from the US orbit. South Korea exported over $149 billion in goods to China in 2017, more than double its exports to the US and six times those to Japan (OEC, 2018). Exports to China accounted for roughly 25% of South Korea’s total exports. Combined with the fact that North Korea, South Korea’s principle adversary, has only China as a real ally, it is possible—evenly likely—that China will be able to exert considerable influence over South Korea’s decision making. More so if there were to be a unified Korea since China would be compelled to increase its involvement in the affairs of a unified Korea to ensure a hostile power aligned with the US did not develop on its border.

Japan’s Response

In both scenarios Japan would be faced with an existential challenge that would fundamentally change its security calculus. The umbrella of a broad US security guarantee is what allows the JSDF to focus on territorial defense, not expeditionary warfare. US nuclear weapons preclude any need for Japan to develop its own nuclear weapons. If that security guarantee is called into question, then Japan would be required to develop offensive capabilities up to and including nuclear weapons.

Taiwan is a danger because of its geographic position astride shipping lanes to Southeast Asia. This risks limiting Japan’s access to its Australian and Indian partners as well as Southeast Asian states like Vietnam by virtue of sea control. Korea presents an age-old challenge in that a unified Korea could be used as a launching point for an invasion of Japan. Moreover, a unified Korea—or even just a South Korea more aligned with China—would likely have less need for US forces stationed on the peninsula. As it is, the Japan-US-South Korea security dynamic hinges on the US. Without the moderating influence of the US, historic grievances between Seoul and Tokyo are likely to manifest themselves and drive further tensions.

Most damningly, Japan will have seen at least one, if not more, US allies and partners be sacrificed for the sake of US interests. Again, this is not to say the US would be in alignment with China, or that it would abdicate its position in East Asia entirely. However, perception is key. The perception that the US is not willing to honor its promises would undermine the trust that holds the US led system together.  Without the US Navy to ensure open access to continental markets, Japan would be compelled to seek closer relations with India, Australia, and possibly Russia as well as build the capacity to self-ensure that access. Japan is already trying to expand its naval ship building capacity to sell submarines to Australia (Gady, 2018). Similarly, Japan and India have steadily increased their defense collaboration on dual use technologies (Economic Times, 2018). Neither of these facts is alarming in their own right, but they lay the groundwork on which future arms agreements and defense cooperation can be built.

This build up would be perceived by its neighbors as unduly aggressive, prompting similar responses by the Chinese, Korean, and even Southeast Asian governments. An insecurity spiral in line with Mearsheimer’s conception of state fear would develop (Mearsheimer, 2004, p. 187). Tensions would force the US to either back Japan and alienate other powers in the region, or push back on Japan weakening the alliance still further until it ultimately came to a breaking point.


In this scenario, China’s rise appears to push the region into conflict yet again. However, this is not an inevitability. The US still retains considerable hard and soft power in the region. Similarly, Japan has done well with its targeted approach to aid and development. No state in the region would benefit from a great power war in East Asia. Therefore, it is possible to avoid the insecurity spiral through an active and consistent diplomatic effort.

One aspect of that diplomacy is Japan’s continued effort to develop good relations with continental powers. Expanding trade with Southeast Asian states along the lines of its 150 projects initiatives is a smart way to maximize Japan’s expertise and resources while countering China’s efforts. The US can and should support this effort either directly or by encouraging allies like Australia, South Korea, and India to coordinate their own efforts to maximize their collective efficiency. This helps build support for both Japan and the broader US order as a source of concrete benefit to states that are most susceptible to China’s economic bullying. Crucially, it also serves as a relatively benign reminder to all parties that the US is invested in the economic and security situation in East and Southeast Asia for the long term.

In that same vein, the US needs to work to reassure traditional allies like Japan and South Korea—and competitors like China and Russia—that it’s security guarantees stand as written. However, that reaffirmation should also come with explicit expectations for American allies. Neither Japan nor South Korea should be allowed to unduly provoke another state in the region. Should they do so against the wishes of the US, those security guarantees would be void. To prevent the appearance that these caveats are intended to help the US avoid honoring its agreements, they should be used sparingly and on critical issues like how to respond in the event of a clash with China as it builds manmade islands in the South China Sea. By limiting the number of exceptions, the US would send a clear message that it will remain a force in the region, but not a reckless or fool hardy one—and that it will not tolerate recklessness on behalf of its allies.

However, Japan must prepare for the worst. Pursuing independent diplomatic relationships with Australia, both Koreas, Russia, India, Southeast Asian states, and especially China is essential if Japan intends to have some say in its geopolitical fate. The sheer number of states in the region means that there is a plethora of relationships that can be built on any number of issues. To a certain extent Japan is already doing this as evidenced by its pursuit of Australian arms contracts and defense cooperation with India. However, defense collaboration cannot be the go-to issue because it will likely make China nervous about Japanese intentions. This is especially so when coupled with Prime Minister Abe’s efforts to rewrite Article 9.

Hence, the major focus of Japan’s diplomacy should be to balance the relationships between the US and its regional allies and China. Japan is likely to be swept into China’s economic orbit by dint of proximity like South Korea and other states. This can be beneficial. Closer ties improve the economic fortunes of all involved. More crucially Japan, South Korea, and the US would constitute a trillion dollar share of China’s overall imports and exports. That is massive leverage if the bloc can be coordinated effectively. Importantly, this should not be pursued to punish China, but to check its excesses.

As China rises, states will need to learn how to operate in the first global multipolar system. Nothing of this scale has ever existed in human history. Japan sits in a precarious position. It is geographically isolated and dependent on relationships with other states for its economic and physical survival. If it were to seek any degree of self sufficiency or assert greater power in the region it would likely trigger an instability spiral that could lead to war. Japan will have to live with a degree of insecurity for the foreseeable future. Yet by pursuing prudent, peaceful, and profitable relationships with other states in the region it can slowly change the perception of those states. This would allow for wider latitude and build trust in a mistrustful area.


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Written by: Lucas Thoma
Written at: University of Arizona
Written for: Dr. Mikhail Beznosov
Date written: April 2019

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