THE ROLE OF THE UNITED STATES IN JAPAN’S POST-1945 SECURITY ARCHITECTURE

https://doi.org/10.57033/mijournals-2026-8-0144 Nizomiddin NUSRATULLAYEV a

a 2nd-Year Student, International Relations Tashkent State University of Oriental Studies, Tashkent, Uzbekistan E-mail: nusratullayevnizomiddin@gmail.com THE ROLE OF THE UNITED STATES IN JAPAN’S POST-1945 SECURITY ARCHITECTURE Abstract. This article analyzes the results achieved through Japan’s defense cooperation with the United States following the Second World War, and examines security cooperation between the two states during the Cold War and the post-Cold War period. The article also reviews the significance of the San Francisco Peace Treaty, the Yoshida Doctrine, and US military bases in Japan for ensuring Japan’s security. Keywords: San Francisco Peace Treaty; pacifist constitution; ANPO; Yoshida Doctrine; US military bases in Okinawa; Cold War; Japan security architecture; SCAP; nuclear umbrella.

INTRODUCTION The conclusion of the Second World War fundamentally transformed not only the global geopolitical map but also the national development strategies and ideologies of states. The country that experienced the sharpest transformation in this regard was, without doubt, Japan. Following its defeat in 1945, Japan was compelled to abandon its militarist policies and traditions and to choose the pacifist and democratic path. The principal reasons for this were: more than sixty major cities including Tokyo, Hiroshima, and Nagasaki had been completely destroyed during the Second World War; more than 40 percent of industrial facilities had been eliminated; and high inflation and famine had exhausted Japan. Moreover, from 1945 to 1952, Japan was administered by SCAP (the Supreme Commander for the Allied Powers) under US General Douglas MacArthur (Dimitria Boria, 2014). Washington’s assumption of responsibility for Japan’s defense and governance in the early postwar years opened the way for Japan to save itself from

Vol. 8, (Issue 2/2026) excessive military expenditure and direct all available resources toward the economic sphere.

Article 9 of the new constitution adopted in 1947 became the legal foundation of this process (National Diet Library, 1947). Under this article, Japan renounced the right to wage war as a means of settling international disputes. This created a natural need for reliance on external forces ekstremistikand specifically on the United States ekstremistikto ensure the country’s defense. The San Francisco Peace Treaty and the Mutual Security Agreement (ANPO) signed in 1951 formalized this partnership (Treaty of Peace with Japan, 1951). US economic and military assistance caused the formation of the “Yoshida Doctrine,” which defined Japan’s postwar foreign policy orientation. The essence of this strategy, advanced by Prime Minister Shigeru Yoshida, was that Japan entrusted its security entirely to the United States and directed all material and human resources toward economic recovery and technological progress. As a result, Japan within a short period became one of the world’s leading economic powers, yet remained in many respects a dependent actor on the international stage. METHODS AND LITERATURE REVIEW The article draws on the conclusions of Japan specialists and researchers, as well as data published in English and Japanese, analytical centers, internet sources, and analytical materials published by the US Department of State. In addition, the works of John W. Dower, Professor at the Massachusetts Institute of Technology ekstremistikspecifically “Embracing Defeat: Japan in the Wake of World War II” ekstremistikand Sheila A. Smith’s “Japan Rearmed: The Politics of Military Power,” alongside other scholarly literature, have been analyzed. Methodologically, the article employs comparative, historical, and content analysis methods.

RESULTS The 1947 Constitution and its consequences. Following the conclusion of the Second World War, as the first criterion for Japan’s transition from militarism to pacifism, Japan’s new peace-oriented constitution was drafted in May 1947 by the Allied Powers under US leadership. Under the constitution, Japan was prohibited from maintaining ground, naval, and air armed forces. Correspondingly, Washington assumed full

responsibility for defending Japan against external threats and any external attack. As a result, Tokyo was freed from spending large sums on military expenditure ekstremistikan average annual saving of approximately 15–20 billion dollars that could instead be invested in automobile and electronics factories such as Sony, Toyota, and Honda rather than in military plants. Furthermore, the relationship between Tokyo and Washington entered a new phase after the war, with American investors, financiers, and businesspeople serving as the main drivers in rebuilding postwar Japan, and Japanese learning from Americans the skills of running, financing, and managing businesses. The San Francisco Peace Treaty (8 September 1951). The San Francisco Peace Treaty is an international agreement that significantly shaped the international order in East Asia following the Second World War. The treaty was formulated on the basis of Washington’s strategic interests; national borders and territorial sovereignty were determined according to the positioning of the defeated countries. The treaty covered vast territories from the Kuril Islands to Antarctica and from Micronesia to the Spratly Islands (Kim, 2012:3). Signed by 48 states, the treaty ended Japan’s occupation and restored its sovereignty in the international arena; however, because of the Cold War, the USSR, Poland, and Czechoslovakia did not sign it.

The US-Japan Security Treaty (ANPO). The security treaty signed in 1951 and updated in 1960 gave Washington the right to maintain military bases in Japan (Avalon Project, 1951). The Peace Treaty recognized that Japan, as a sovereign state, had the right to conclude collective security agreements. The United States expressed readiness to keep part of its armed forces in and around Japan for the sake of peace and security, while requiring Japan to assume increasing responsibility for defending itself against direct and indirect aggression and to refrain from any action beyond ensuring peace and security in conformity with the purposes and principles of the UN Charter. The treaty’s key articles established: the US right to station land, air, and naval forces in and around Japan (Article I); Japan’s prohibition from granting base or transit rights to any third party without prior US consent (Article II); conditions for US forces in Japan to be governed by inter-governmental agreements (Article III); and conditions for the treaty’s termination when adequate alternative security arrangements come into force (Article IV). The 1951 ANPO treaty became the cornerstone of the strategy of handing Japan’s security to Washington while pursuing economic development.

Vol. 8, (Issue 2/2026) The Cold War period: US-Japan relations. With the onset of the Cold War, US policy toward Japan shifted from demilitarization to a strategy of containing communism. Japan became one of the United States’ principal partners in East Asia for containing communism. US assistance in this period manifested in two directions. First, Japan was provided with a “nuclear umbrella,” which enabled it to keep defense expenditure at below one percent of GDP. Second, large-scale US military procurement from Japan during the Korean War (1950–1953) pulled the country’s industry out of crisis. US military bases in Okinawa provide Japan with a reliable shield against potentially aggressive forces in the region such as China and North Korea, and offer the capability to mount a rapid response should any military action be taken against Japan. The Yoshida Doctrine. During the Allied occupation of Japan after the Second World War, Prime Minister Shigeru Yoshida developed the postwar foreign and security policy concept known as the “Yoshida Doctrine.” The term was coined in 1977 by the noted expert Masashi Nishihara as a way of defining the consistent, pragmatic strategy of postwar Japan (Nishihara, 2016:123). Masataka Kosaka described the doctrine as follows: “Japan ensures its national security by forming an alliance with the United States and maintains a minimal self-defense capability, with the result that Japan directs saved resources toward economic activities for the development of the country” (Kosaka, 2016:123). Prime Minister Yoshida used his country’s weakness as a diplomatic tool: Japan exploited the United States’ fear of the spread of communism to extract economic assistance and favorable trade terms.

If military expenditure stood at 44 percent of GDP in 1934, 75 percent in 1941, and 90 percent in 1944, following the war ekstremistikwith the United States assuming responsibility for Japan’s security, the adoption of the new constitution, the Yoshida Doctrine, and the shift to pacifism ekstremistikit fell to 6 percent in the 1960s and has not exceeded 1 percent since 1976 (Ministry of Defense of Japan, n.d.). US military bases in Okinawa. US forces entered Okinawa in April 1945 during the Battle of Okinawa, one of the most significant battles of the Second World War. After the war ended, Washington retained administrative control of the island. Only in 1972 was Okinawa legally returned to Japan, though under the security treaty it was agreed that US military bases would remain there (Ministry of Foreign Affairs of Japan, 1972). All five US military service branches (Marine Corps, Air Force, Navy, Army, and Space

Force) are present in Okinawa, with approximately 30,000 military personnel in total. The principal air base is Kadena Air Base ekstremistikthe largest US air base in the Pacific, housing F-15, F-22, and F-35 fighter aircraft, long-range reconnaissance aircraft, and aerial refueling aircraft, with Patriot missile defense systems also installed on the island. The Marine Corps constitutes the largest contingent in Okinawa, organized around the III Marine Expeditionary Force (U.S. Forces Japan, 2026). Okinawa’s strategic importance is connected with its geographic position. The sea lanes near Okinawa constitute the main corridor for the Chinese Navy’s access to the open Pacific, and the presence of bases here allows Tokyo and Washington to monitor and control these movements. Okinawa is located only 600 km from Taiwan (with the outermost island of Yonaguni a mere 110 km away), making it the nearest rapid-response operational center in any potential Taiwan Strait conflict. The disputed Senkaku Islands between Japan and China also fall within Okinawa’s administrative jurisdiction, with US military bases serving as a deterrent to their protection. Aircraft operating from Kadena can rapidly detect North Korean missile tests and respond if necessary. Post-Cold War period: The 1996 Declaration and the 2026 Alliance Initiative. One of the important agreements of the post-Cold War period is the “US-Japan Joint Declaration on Security,” signed in 1996 by President Bill Clinton and Prime Minister Ryutaro Hashimoto. The principal reasons for its conclusion were to strengthen the Washington-Tokyo alliance after the Cold War and to respond to China’s military assertiveness and North Korean missile threats. The agreement enabled the United States to maintain 100,000 troops in the Pacific region (Ministry of Foreign Affairs of Japan, 1996). Washington and Tokyo also strengthened practical cooperation on joint research and development of missile defense systems. The 1996 treaty led Japan to review the role of its Self-Defense Forces (JSDF) on an international scale, with Japan subsequently cooperating with the United States in UN peacekeeping operations and humanitarian assistance ekstremistikfor example, providing logistical support in Iraq reconstruction and Indian Ocean counterterrorism operations.

One of the most recent and important agreements is the “New Initiatives to Strengthen the US-Japan Alliance,” signed in Washington on 19 March 2026, between President Donald Trump and Prime Minister Sanae Takaichi (The White House, 2026). The agreement covers the following commitments: co-production of SM-3 Block IIA

Vol. 8, (Issue 2/2026) missiles (for missile defense) at a fourfold increase in output, and commencement of practical joint production of AMRAAM (air-to-air) missiles; confirmation that US Typhon medium-range missile systems will be deployed on Japanese territory; upgrading of the command structure through the Japan-Japan Operational Command (JJOC) established in March 2025; a Japanese commitment to invest 550 billion dollars in US economic sectors related to national security; and final technical agreement on Japanese astronauts landing on the lunar surface under NASA’s Artemis program and on the use of a Japanesedeveloped pressurized lunar rover (Johnstone, 2026). As of 2026, Japan hosts more than 55,000 US military personnel and 85 military installations (US Department of Defense, 2026).

DISCUSSION Although the US-Japan alliance provides security guarantees, it also creates a number of problems for Japanese society and sovereignty. For example, more than 70 percent of US military naval and air bases are located in Okinawa, which constitutes only 0.6 percent of Japan’s territory. This creates concerns for local residents regarding noise, environmental pollution, and the risk of technical accidents. The Status of Forces Agreement (SOFA) grants US military personnel certain legal privileges in Japan, meaning that local police and the judicial system cannot hold them fully accountable. This makes it impossible to deliver fair punishment for killings and accidents caused by US military personnel. The strong military dependence also means that Japan is at high risk of becoming involuntarily entangled in Washington’s regional conflicts ekstremistikfor example, in clashes over Taiwan or the South China Sea. Australian National University Emeritus Professor Gavan McCormack, in his work “Client State: Japan in the American Embrace,” characterizes Japan as a “vassal state” dependent on the United States (McCormack, 2007:4). In his view, Tokyo has surrendered its independent foreign policy in exchange for Washington’s security umbrella, and there are those within Japanese society who affirm this characterization. The events analyzed above demonstrate that although Japan’s handing over of its defense to the United States has served as an important support for its economic development and for ensuring regional security, it has also caused Japan’s inability to make free decisions in

foreign policy and the existence within Japanese society of those who doubt to some degree that Japan is a fully sovereign state.

CONCLUSION In conclusion, Japan’s postwar path of development created a unique model. On one hand, by entrusting its security entirely to the United States and coming under a “nuclear umbrella,” Japan was able to sharply reduce military expenditure and devote available resources to creating the “Japanese economic miracle,” becoming a technological giant, raising living standards, and presenting itself as a peace-loving state. On the other hand, as scholars such as Gavan McCormack emphasize, Japan has in practice surrendered its independent foreign policy and has fallen to some degree into the status of a “client state” (vassal). In particular, legal inequality (the failure of US military personnel to fully comply with local laws) and the occupation of strategic territories by foreign bases have consistently placed questions of national pride and sovereignty on the agenda (McCormack, 2007). In brief, although Japan has guaranteed its security through its alliance with the United States and ensured regional security, this partnership has also made Japan indirectly complicit in Washington’s strategic designs. REFERENCES 1. Avalon Project. (1951). Security treaty between the United States and Japan. Yale Law School, Lillian Goldman Law Library. https://avalon.law.yale.edu/20th_century/japan001. asp 2. Center for Strategic and International Studies. (2026). Deepening strategic alignment: Priorities for the U.S.-Japan alliance. https://www.csis.org/analysis/deepening-strategicalignment-priorities-us-japan-alliance 3. Dimitria Boria, G. (2014). Japan and the United States: The postwar occupation and its legacy. [Publisher not specified].

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