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Introduction: An Alliance Renewed? Future-proofing U.S.-Japan Security Relations

About this Volume

Authors of this volume participated in the inaugural U.S.-Japan Next-Generation Leaders Initiative, sponsored by the U.S. Department of State, through the U.S. Embassy Tokyo. With backgrounds from academia, government, military and industry, the cohort brings rich insights on the past, present, and future of the U.S.-Japan bilateral security relations.

The statements made and views expressed are solely the responsibility of the authors and do not necessarily reflect the views of their respective organizations and affiliations. Pacific Forum’s publications do not necessarily reflect the positions of its staff, donors and sponsors.

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On September 8, 1951, the Security Treaty between the United States and Japan was signed, marking the beginning of an alliance relationship that would serve as the cornerstone of regional peace, security, and prosperity in the decades that followed. Forged in the aftermath of the Second World War, at a time when a new post-war international order was being crafted around the United Nations, and an emergent superpower rivalry between the United States and the Soviet Union was taking shape, the alliance has endured both economic shocks and geopolitical change. The alliance’s resilience is partly due to its ability to adapt to the changing strategic environment enabled by the willingness of both sides to reconcile, compromise,  and prioritize the welfare and security of their peoples. In 1960, the relationship evolved significantly. The Security Treaty was replaced by the Treaty of Mutual Cooperation and Security, granting the United States a permanent presence in Japanese territories in exchange for defending Japan in the event of an armed attack.

When the Cold War ended, the alliance did not fall into obscurity. Instead, it continued to adapt. Alliance managers found negotiating expectations and future responsibilities prudent given new realities. This culminated in the release of the Guidelines for Japan-U.S. Defense Cooperation in 1997. The Guidelines created a “solid basis for more effective and credible U.S.-Japan cooperation under normal circumstances, in case of an armed attack against Japan, and in situations in areas surrounding Japan.” Soon after the 9/11 terrorist attacks, the Japanese Self-Defense Forces (SDF) were dispatched in support of combat operations  overseas for the first time, initially to the Indian Ocean to assist U.S. operations in Afghanistan, but later also to Iraq to help in reconstruction. The SDF continued to carve out a broader international role by engaging in Humanitarian Assistance and Disaster Relief (HADR) operations in South and Southeast Asia. Regional countries welcomed Japan’s de facto armed forces to their shores, alongside those of the United States, as they coped with natural disasters such as the Boxing Day tsunami in 2004 that impacted countries like Indonesia, Thailand, Myanmar, India, and Sri Lanka, and Typhoon Haiyan in 2013 that killed over 6,000 in the Philippines.

Meanwhile, as North Korea pressed on with its nuclear and missile development programs in violation of multiple UN Security Council Resolutions, and as the region grows weary of the security implications of China’s rise, including effort to operationalize illegal claims in many of the region’s maritime commons, the U.S.-Japan alliance remained responsive. In 2015, Japanese policymakers reinterpreted their constitution and allowed the SDF to exercise the right to collective self-defense, for instance, by defending U.S. vessels subjected to an armed attack. Japan’s embrace of collective self-defense, already enshrined in the UN Charter, resulted in the revision of the 1997 Guidelines for Japan-U.S. Defense Cooperation, making the alliance even more relevant to the rapidly changing security environment.

In 2022, the alliance is, in many ways, at a crossroads. The United States, under the Trump and Biden administrations, is no longer an anchor of trade liberalization, and both administrations have sought to recalibrate U.S. relationships with close allies in the context of growing challenges to the rules-based order that defined the last three decades. While the alliance has endured, there are challenges, some of which are domestic, that will continue to test the security relationship. For instance, the planned relocation of Marine Corps Air Station Futenma, which to many Okinawans does not address the overwhelming presence of the U.S. military in Okinawa, the issue of burden sharing in the alliance, the defense of Taiwan, and the demand for Tokyo to dramatically increase defense budget to over 1% of GDP to better cope with the increasingly unfavorable regional balance of power will persist and have to be managed. It is vital that next-generation Japanese and Americans are involved in these economic and security discourses and are mutually invested in the growth of their countries’ partnerships.

It is within this context of change, with the challenges confronting the U.S.-Japan alliance in flux, that our contributors shed light on some of those critical questions that will undoubtedly define not just the future of U.S.-Japan relations but the trajectory of international order in the coming years. This collection of papers includes contributions from emerging voices in academia, government, and the armed forces. It is a timely intervention that takes into account strategic competition between Washington and Beijing, the impact of Russia’s February 2022 invasion of Ukraine on international order, and heightened tensions over Taiwan.

This collection of papers begins with contributions that explore how the alliance will continue to evolve in the face of emergent challenges. Indeed, the first paper by Jada Fraser places an emphasis on rethinking how the United States can more effectively harness its alliance relationships in East Asia to advance shared interests and counter emerging threats. Fraser identifies the “advantages of organizing the U.S.-Japan-ROK trilateral as a form of flexible multilateralism based on overlapping frameworks of cooperation rather than a formally binding agreement.”

The second contribution to this volume, by Cassie Rodriguez, examines how U.S. relationships in East Asia are shifting from a more traditional network of ‘hub-and-spokes’ security arrangements to a ‘minilateralist’ approach that favors informal alignments of countries that are more targeted and issue-specific. For Rodriguez, the U.S.-Japan alliance could become a model for minilaterlism and a driver for the establishment of robust, yet flexible small groupings of states working closely together on shared challenges. An example of this is the Quad.

The next two papers offer insights from international relations theory. Yu Inagaki draws on Kosaka Masataka’s power, interests, and norms framework to offer recommendations for both the United States and Japan to bring both countries into closer alignment. Meanwhile, Shusuke Ioku presents quantitative data analyses of territorial aggression and formal modeling of gray zone conflicts to argue that the key to deterring gray zone coercion is helping sustain the presence of Southeast Asian claimants through capacity building related to reinforcement of presence, constant naval and air patrols, and other measures that would allow them to withstand low-level aggression without backing down. Ioku recommends that Japan and the United States channel limited recourses accordingly and not be content with symbolic joint exercises and rhetorical support for rules-based resolution of disputes.

The next four papers delve deeper into issue-specific areas and contingencies that present challenges and opportunities for the U.S.-Japan alliance going forward. First, Ayae Yoshimoto provides Japan’s perspective on heightened tensions over Taiwan. Offering recommendations that aim to bolster Taiwan’s own position and image in the international community alongside more practical observations relating to a Taiwan contingency, Yoshimoto underlines the critical importance of Taiwan for Japan’s national security. Next, Rena Sasaki provides a more granular analysis of the legislative, regulatory, and political constraints that a more limited Taiwan contingency scenario would pose for Tokyo. Both Yoshimoto and Sasaki underline how Taiwan contingencies demonstrate the urgent need for Tokyo and Washington to bolster crisis response mechanisms.

Shinichi Hirao then turns to examine how NATO standards can enhance the U.S.-Japan alliance. Benchmarking against NATO’s core tasks of Deterrence and Defense, Crisis Management, and Cooperative Security, as outlined in the 2022 Strategic Concept, Hirao draws lessons for the U.S.-Japan security relationship. Hirao also concludes by offering specific recommendations to Tokyo for defense procurement. The final paper of this collection, by Brittany Bradley-Marcial, explores the question of bringing Japan into the Five Eyes community, analyzing both the rationale and the obstacles to membership, as well as potential paths forward that could bring Japan into a closer intelligence sharing relationship with the Five Eyes.

In sum, each contribution to this volume contains new insights into the U.S.-Japan alliance from the next generation of scholars, decision-makers, or military leaders. To be sure, this collection of papers attests to one of the critical factors that explains the longevity of the U.S.-Japan alliance: the alliance’s continuous ability to remake itself in the face of new and emerging challenges.

PhotoU.S. Marines display the American and Japanese flag attached to the M777’s for the Friendship Festival on May 11, 2019, at Combined Arms Training Center Camp Fuji, Shizuoka, Japan. Source: U.S. Marine Corps photo by Pfc. Karis Mattingly/ Public Domain