What is ANZUS?
Answer
Military alliance with New Zealand and the US
Explanation
ANZUS is a tripartite security treaty between Australia, New Zealand, and the United States, signed in San Francisco on 1 September 1951 and in force from 29 April 1952. The treaty commits each country to consult and to act to meet common danger if any of the three is attacked in the Pacific region. ANZUS remains the foundation of Australia's alliance relationship with the United States.
The treaty was negotiated by Australian External Affairs Minister Percy Spender and signed at the same conference at which Japan signed its peace treaty with the wartime Allies, ending the formal occupation of Japan. Australia and New Zealand sought a security guarantee from the United States in part because of concern about Japan's future remilitarisation, and the treaty took shape against the broader background of the Korean War (1950 to 1953) and early Cold War alignment.
ANZUS has been invoked in important moments. After the 11 September 2001 attacks on the United States, Prime Minister John Howard formally invoked the treaty for the first and only time in its history. Australia subsequently joined the United States-led coalitions in Afghanistan from 2001 and Iraq from 2003. Joint exercises like Talisman Sabre, shared intelligence arrangements like the Five Eyes (Australia, the United States, the United Kingdom, Canada, and New Zealand), and the basing arrangements at facilities like Pine Gap in central Australia all flow from the ANZUS framework.
New Zealand's participation in ANZUS has been complicated since 1986, when the United States suspended its security obligations to New Zealand after the Lange Labour government banned nuclear-armed and nuclear-powered ships from New Zealand ports. The treaty remains in force as a tripartite instrument, but the Australia-United States and Australia-New Zealand legs operate separately in practice. The AUKUS partnership of 2021 between Australia, the United Kingdom, and the United States, which includes the planned construction of nuclear-powered submarines, has further deepened Australia's alliance with the United States outside the original ANZUS framework.
Why this matters for your test
ANZUS frames Australia's most important defence relationship, and knowing the 1951 founding date and the post-9/11 invocation gives new citizens the basic shape of the country's foreign policy.
Source: Australian Citizenship: Our Common Bond (2024)
