Historical sources on the ANZUS and SEATO treaties
The Cold War led to the creation of several military alliances that sought to protect nations from potential attack and to limit the spread of communism.
In the Pacific region, the 1951 ANZUS Treaty united Australia, New Zealand, and the United States in a pact of mutual defence, which declared that an armed attack on one member would threaten the safety of all.
Soon after, the Southeast Asia Treaty Organization (SEATO) formed in 1954 as another security alliance designed to prevent communist expansion in Asia.
The following sources explore how these alliances formed, why governments created them, and how they influenced international relations during the Cold War.
Source 1
"Security Treaty Between the United States, Australia, and New Zealand (ANZUS); September 1, 1951(1)
The Parties to this Treaty,
Reaffirming their faith in the purposes and principles of the Charter of the United Nations and their desire to live in peace with all peoples and all Governments, and desiring to strengthen the fabric of peace in the Pacific Area,
Noting that the United States already has arrangements pursuant to which its armed forces are stationed in the Philippines,(2) and has armed forces and administrative responsibilities in the Ryukyus, and upon the coming into force of the Japanese Peace Treaty may also station armed forces in and about Japan to assist in the preservation of peace and security in the Japan Area,(3)
Recognizing that Australia and New Zealand as members of the British Commonwealth of Nations have military obligations outside as well as within the Pacific Area,
Desiring to declare publicly and formally their sense of unity, so that no potential aggressor could be under the illusion that any of them stand alone in the Pacific Area, and
Desiring further to coordinate their efforts for collective defense for the preservation of peace and security pending the development of a more comprehensive system of regional security in the Pacific Area,
Therefore declare and agree as follows:…
Each Party recognizes that an armed attack in the Pacific Area on any of the Parties would be dangerous to its own peace and safety and declares that it would act to meet the common danger in accordance with its constitutional processes."
IN WITNESS WHEREOF the undersigned Plenipotentiaries have signed this Treaty.
DONE at the city of San Francisco this first day of September, 1951."
Contextual information:
This is the official text of the ANZUS Security Treaty as published in the United States Government volume American Foreign Policy 1950–1955: Basic Documents, compiled by the U.S. Department of State and printed by the U.S. Government Printing Office in 1957. It records the agreement between the United States, Australia, and New Zealand, setting out their mutual commitments to consult and act together for collective defence in the Pacific region during the early Cold War.
Bibliographical reference:
United States Department of State. (1957). Security Treaty between the United States, Australia, and New Zealand (ANZUS); September 1, 1951. In American foreign policy 1950–1955: Basic documents (Vol. 1, pp. 3423–3425). U.S. Government Printing Office. (Text accessed via Yale Law School Avalon Project.)
Copyright: The treaty text and the American foreign policy 1950–1955 volume are works of the U.S. federal government and are in the public domain.
Source 2
"Throughout the period of the negotiation of the tripartite security treaty among Australia, New Zealand, and the United States signed at San Francisco on September 1, 1951 (the ANZUS Treaty) there were constant references to broader security arrangements affecting the Pacific area. United States policy since late 1949 (as expressed in NSC 48/2) had been that the United States Government had great sympathy with non-Communist, indigenous efforts in Asia to form regional associations based on self-help and mutual aid and that if such associations were brought into being it was willing to consider ways in which it might assist them. By the beginning of 1951, however, the United States had decided that it was desirable to take a more active role in building a security system in the Pacific area."
"The ANZUS Treaty was finally signed as one in a series of security agreements which were related in a broad sense although not tied together by their terms. The other instruments in this series were the Philippine-American security treaty, the Japanese-American Security treaty, and the Japanese peace treaty. It was clearly understood that Australian and New Zealand concurrence in a Japanese peace treaty which would permit the rearmament of Japan was conditioned on the conclusion of the ANZUS security pact, and that the American desire for wider security arrangements in the Pacific found expression in the bilateral treaties with Japan and the Philippines which were concluded at the same time."
Contextual information:
This background paper was prepared in 1952 by the Division of Historical Research of the U.S. Department of State for Secretary of State Dean Acheson before an ANZUS Council meeting in Honolulu. It explains how ANZUS fitted into a wider Cold War strategy of building security arrangements with non‑communist countries in the Pacific and Asia, and shows that the treaty was closely linked to U.S. efforts to contain communist influence and manage Japanese rearmament.
Bibliographical reference:
U.S. Department of State, Division of Historical Research. (1952, July 24). References in the negotiation of the ANZUS Treaty to broader security arrangements affecting the Pacific area (Background paper for ANZUS Council, Honolulu). Harry S. Truman Presidential Library and Museum.
Copyright: As a work prepared by U.S. federal government officials in the course of their duties, this document is in the public domain.
Source 3
"In September of 1954, the United States, France, Great Britain, New Zealand, Australia, the Philippines, Thailand and Pakistan formed the Southeast Asia Treaty Organization, or SEATO. The purpose of the organization was to prevent communism from gaining ground in the region. Although called the "Southeast Asia Treaty Organization," only two Southeast Asian countries became members. The Philippines joined in part because of its close ties with the United States and in part out of concern over the nascent communist insurgency threatening its own government. Thailand, similarly, joined after learning of a newly established "Thai Autonomous Region" in Yunnan Province in South China, expressing concern about the potential for Chinese communist subversion on its own soil."
Contextual information:
This passage comes from the U.S. Department of State’s Milestones: 1953–1960 series, produced by the Office of the Historian. It describes the formation of the Southeast Asia Treaty Organization (SEATO) in 1954 and clearly states that its purpose was to prevent communism from gaining ground in Southeast Asia, placing SEATO within the wider U.S.-led containment strategy of the Cold War.
Bibliographical reference:
Office of the Historian, U.S. Department of State. (n.d.). Southeast Asia Treaty Organization (SEATO), 1954. In Milestones: 1953–1960 – Office of the Historian. (Archived version retrieved from the Internet Archive.)
Copyright: Works produced by the U.S. federal government are in the public domain.
Source 4
"At the prompting of U.S. Secretary of State John Foster Dulles, a coalition of nations forms the Southeast Asia Treaty Organization (SEATO), intended as a military alliance to check Communist expansion. Among its members are France, Great Britain, the United States, Australia, New Zealand, the Philippines, Thailand, and Pakistan. Geneva Accords restrictions do not permit South Vietnam, Cambodia, or Laos to participate. But SEATO does include a separate protocol designating the Associated States as areas that must be protected to ensure the “peace and security” of the signatories. This protocol establishes a foundation for future intervention in Indochina."
Contextual information:
This extract is from the United States of America Vietnam War Commemoration website, an official U.S. Department of Defense educational project summarising key events of the Vietnam War era. It explains who created SEATO, lists the eight member countries, and notes that the organization was designed as a military alliance to check communist expansion in Southeast Asia.
Bibliographical reference:
U.S. Department of Defense. (n.d.). Southeast Asia Treaty Organization – September 8, 1954. United States of America Vietnam War Commemoration.
Copyright: As an official work prepared for a U.S. Department of Defense commemorative program, this content is in the public domain.
Source 5
"The Armed Forces Research Institute of Medical Sciences (AFRIMS) in Bangkok, Thailand, originated in 1959 through an agreement between the governments of the United States and Thailand. The original laboratory was created as the Southeast Asia Treaty Organization's (SEATO's) Cholera Research Laboratory. The laboratory was expanded in 1961 to include research on other tropical diseases and was renamed the SEATO Medical Research Laboratory. SEATO was dissolved in 1977, and the U.S. component of AFRIMS was reorganized as a joint Royal Thai Army-U.S. Army medical research laboratory under the overall command of a Royal Thai Army Officer of flag rank."
Contextual information:
This paragraph comes from a chapter on the Armed Forces Research Institute of Medical Sciences in a U.S. government publication hosted by the National Center for Biotechnology Information (NCBI) Bookshelf. While the main focus is medical research, it clearly states that SEATO was dissolved in 1977.
Bibliographical reference:
Armed Forces Health Surveillance Center. (2011). GEIS at the Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand. In Institute of Medicine (U.S.), Global infectious disease surveillance and detection: Assessing the challenges—finding solutions (Chapter section). National Academies Press.
Copyright: U.S. government material on NCBI Bookshelf is public domain.
Source 6
"The North Atlantic Treaty was signed at Washington, DC on April 4, 1949 and entered into force on August 24, 1949. The treaty, in English and French texts, formed the legal basis of and is implemented by the North Atlantic Treaty Organization (NATO). Representatives of the United States, Canada, and 10 Western European nations signed a mutual defense pact against possible aggression from the Soviet Union."
Contextual information:
This passage comes from a teaching resource on the North Atlantic Treaty hosted by the U.S. National Archives’ DocsTeach platform. It explains that the North Atlantic Treaty (NATO) was signed in Washington in 1949 as a mutual defence pact between the United States, Britain and other Western European countries.
Bibliographical reference:
National Archives and Records Administration. (n.d.). North Atlantic Treaty. DocsTeach.
Copyright: U.S. National Archives descriptive texts and images of U.S. government records are public domain.
Source 7
"The Parties to this Treaty reaffirm their faith in the purposes and principles of the Charter of the United Nations and their desire to live in peace with all peoples and all governments. They are determined to safeguard the freedom, common heritage and civilisation of their peoples, founded on the principles of democracy, individual liberty and the rule of law. They seek to promote stability and well-being in the North Atlantic area. They are resolved to unite their efforts for collective defence and for the preservation of peace and security.
They therefore agree to this North Atlantic Treaty:"
Contextual information:
This is the opening preamble of the official text of the North Atlantic Treaty as published by the North Atlantic Treaty Organization (NATO). It outlines NATO’s purpose in safeguarding freedom and uniting member states for collective defence and the preservation of peace and security.
Bibliographical reference:
North Atlantic Treaty Organization. (1949). The North Atlantic Treaty (Preamble). NATO Official Texts.
Copyright: Public Domain.
Source 8
"New Zealand’s relationship with the United States in the post-World War II period was closely associated with the 1951 Australia-New Zealand-United States (ANZUS) security treaty, under which signatories agreed to consult in case of an attack in the Pacific and to “act to meet the common danger.” This changed in the 1980s, when New Zealand’s implementation of a policy barring nuclear-armed and nuclear-powered warships from its ports effectively prevented practical alliance cooperation under ANZUS. In 1986, the United States suspended its ANZUS security obligations to New Zealand."
Contextual information:
This paragraph is from a U.S. Department of State fact sheet on relations with New Zealand. It clearly links New Zealand’s decision to bar nuclear‑armed and nuclear‑powered ships from its ports with the U.S. decision in 1986 to suspend its ANZUS security obligations to New Zealand.
Bibliographical reference:
U.S. Department of State. (2020, November 30). U.S. relations with New Zealand (Fact sheet). Bureau of East Asian and Pacific Affairs.
Copyright: U.S. federal government publications are in the public domain.
Source 9
“At the prompting of U.S. Secretary of State John Foster Dulles, a coalition of nations forms the Southeast Asia Treaty Organization (SEATO), intended as a military alliance to check Communist expansion. Among its members are France, Great Britain, the United States, Australia, New Zealand, the Philippines, Thailand, and Pakistan. Geneva Accords restrictions do not permit South Vietnam, Cambodia, or Laos to participate. But SEATO does include a separate protocol designating the Associated States as areas that must be protected to ensure the ‘peace and security’ of the signatories. This protocol establishes a foundation for future intervention in Indochina.”
Contextual information:
This summary is from the official U.S. Department of Defense Vietnam War Commemoration website, which provides a chronological overview of key events leading up to and during the Vietnam War.
Bibliographical reference:
United States of America Vietnam War Commemoration. (n.d.). Southeast Asia Treaty Organization, September 8, 1954 (event summary). Washington, DC: U.S. Department of Defense.
Copyright: Public domain
Source 10
“The Security Treaty between Australia, New Zealand and the United States of America (the ANZUS Treaty) which came into force on 29 April 1952 is a key element supporting Australia’s national security. … It is a result of this environment that the Treaty was first invoked following the 11 September 2001 terrorist attacks on the United States (US).”
Contextual information:
This extract comes from a report of the Joint Standing Committee on Foreign Affairs, Defence and Trade of the Parliament of Australia, reviewing Australia’s defence relations with the United States.
Bibliographical reference:
Joint Standing Committee on Foreign Affairs, Defence and Trade. (2006). Australia’s defence relations with the United States (Foreword, para. 2). Canberra, ACT: Parliament of the Commonwealth of Australia.
Source 11
“Whereas the United States and Australia signed the Security Treaty among Australia, New Zealand, and the United States of America (referred to in this resolution as the ‘ANZUS Treaty’) in San Francisco on September 1, 1951; … Whereas Australia is the only party to the treaty to invoke Article IV of the ANZUS Treaty, done so on September 14, 2001, in response to the terrorist attacks on the United States on September 11, 2001, in a show of stalwart support for the American people; …”
Contextual information:
This quotation is from a 2021 concurrent resolution of the United States Senate commemorating the seventieth anniversary of the ANZUS Treaty.
Bibliographical reference:
U.S. Senate. (2021). S. Res. [unnumbered draft]: Commemorating the 70th anniversary of the signing of the Security Treaty among Australia, New Zealand, and the United States of America (pp. 1–3). 117th Congress, 1st Session.
Copyright: Public domain (U.S. federal legislative document).