Anzus Agreement 1951

The ANZUS Agreement 1951: A Brief Overview

The ANZUS Agreement 1951, also known as the Australia, New Zealand, United States Security Treaty, is a collective defense agreement between Australia, New Zealand, and the United States. This agreement was signed on September 1, 1951, in San Francisco, California, and came into effect in 1952. The ANZUS Agreement was created to promote security, cooperation, and mutual defense among the three nations.

Background of ANZUS Agreement

The ANZUS Agreement was created in the context of the Cold War. The Soviet Union had become a major threat to the Western world, and the United States was leading efforts to contain Soviet influence. The United States sought to create alliances with countries that shared a common interest in maintaining peace and security. Australia and New Zealand were ideal partners, given their location in the Pacific region and their shared values with the United States.

Key Provisions of ANZUS Agreement

The ANZUS Agreement has several key provisions that outline the responsibilities and obligations of the signatories. These provisions include:

1. Collective Defense: The signatories must take collective action to deter or respond to an armed attack against any one of them.

2. Consultation: The signatories must consult with each other if they believe their security is threatened.

3. Military Cooperation: The signatories must cooperate with each other on military matters, such as training exercises and intelligence sharing.

4. Nuclear Weapons: The signatories must not use nuclear weapons against each other or encourage the proliferation of nuclear weapons.

ANZUS Agreement Today

The ANZUS Agreement remains in effect today, although it has evolved over time. In 1985, New Zealand passed laws prohibiting nuclear-armed or nuclear-powered ships from entering its ports, which caused a rift in the alliance. As a result, the United States suspended its obligations to New Zealand under the ANZUS Agreement, effectively ending military cooperation between the two countries. Today, the ANZUS Agreement primarily serves as a symbol of the strong ties between Australia, New Zealand, and the United States.


The ANZUS Agreement 1951 is a significant milestone in the history of the Pacific region. It reflects the commitment of Australia, New Zealand, and the United States to promote security, cooperation, and mutual defense. Although the alliance has faced challenges over the years, it continues to play an important role in maintaining regional and global peace. As such, the agreement remains an important component of international security.