When was the ANZUS treaty signed and when did it enter into force?
The ANZUS treaty was signed on the 1st of September 1951 in San Francisco. It entered into force on the 29th of April 1952.
Questions about ANZUS
Short answers, pulled from the story.
Why was New Zealand suspended from ANZUS?
New Zealand was partially suspended from ANZUS in 1986 after it barred nuclear-powered and nuclear-armed ships from its ports and waters. The United States suspended its treaty obligations to New Zealand because the policy denied access to all US Navy vessels, given the US Navy's policy of neither confirming nor denying the presence of nuclear weapons aboard its ships.
What was the USS Buchanan incident and why did it matter for ANZUS?
In February 1985, New Zealand refused a port-visit request for the USS Buchanan, a guided-missile destroyer capable of launching nuclear depth bombs. The refusal was especially provocative because New Zealand had unofficially invited the United States to send a ship. The United States interpreted it as a deliberate slight and it triggered the suspension of US treaty obligations to New Zealand.
What was the Rainbow Warrior bombing and how did it affect New Zealand's foreign policy?
On the 10th of July 1985, agents of the French Directorate-General for External Security bombed the Greenpeace vessel Rainbow Warrior in Auckland, killing one person. The muted response from Western leaders hardened New Zealand public opinion against nuclear technology and accelerated New Zealand's shift toward building relationships with small South Pacific nations rather than relying on traditional military allies.
When did New Zealand and the United States restore their defence relationship after the ANZUS split?
Cooperation quietly resumed across eight areas in 2007. The Wellington Declaration of 2010, signed during a visit by US Secretary of State Hillary Clinton, formally defined a new strategic partnership. On the 20th of September 2012, US Secretary of Defense Leon Panetta announced the lifting of the 26-year-old ban on New Zealand warship visits to US military bases.
Does the ANZUS treaty apply to a Chinese attack on Taiwan?
The question has never been definitively settled. In March 2005, Australian Foreign Minister Alexander Downer stated that Chinese aggression against Taiwan would bring the treaty into force but would require only consultations with the United States and would not necessarily commit Australia to war. The treaty's language obligates signatories to act in accordance with their constitutional processes, not to automatically enter armed conflict.