Australia's security relationships

Stephen Fallon, Foreign Affairs, Defence and Security

Key issue

As a middle power in an era of increasing great-power competition, Australia lacks the strategic weight to single-handedly ensure its own security. Throughout its history, it has chosen to ally with great powers: initially Great Britain, before realigning towards the US during the Second World War. Australia has fought alongside them as a junior partner in conflicts in Europe, Asia and the Middle East to forge enduring relationships and maximise the probability that they would defend Australia were it threatened.

Australian concerns about the trajectory of a more aggressive China have driven the ANZUS alliance, typically referred to as the Alliance, to greater levels of intimacy. However, Australia’s efforts to build stronger relationships with both old and new partners, such as Japan and India, suggests that it has long-term concerns about the reliability of its alliance with the US and is seeking to mitigate future risks by diversifying its range of security partners.

The ANZUS alliance

Australia’s alliance with the US is the cornerstone of its strategic policy. Its close ties to the US provide it with a variety of benefits, including access to US intelligence, cutting-edge military technology, military exercise opportunities and access to US defence and foreign affairs decision-makers that is arguably disproportionate for a country with Australia’s limited strategic weight. The alliance enhances the lethality of the Australian Defence Force (ADF) via access to intelligence and military technology, while defence analysts broadly agree that achieving strategic independence would cost more but fail to deliver a similar level of defence capability.


The ANZUS alliance was formed in 1951 by a trilateral security treaty between Australia, New Zealand and the US. Designed to ensure the security of the Pacific region throughout the Cold War, the treaty has only been formally invoked once – by former Australian prime minister, John Howard, in response to the September 11 attacks on the US.

The treaty was energetically pursued by Australia (and New Zealand), with the US demonstrating some reluctance. Australia’s desire for a security treaty with the US was driven by concerns about US plans to rebuild Japan as a bulwark against communism. Notably, it was the first example of Australia forming a political alliance without British involvement. Though Britain believed it should be included as the head of the Commonwealth, and campaigned to be a signatory, Australia, New Zealand and the US rebuffed its efforts.

Though Australia and New Zealand participated in Cold War conflicts such as the Korean and Vietnam wars, they did not do so under the framework of ANZUS. The alliance was challenged after the 1984 New Zealand general election, which brought the New Zealand Labour Party to power with a commitment to make New Zealand ‘nuclear free’. As a result, the New Zealand Government refused to permit US naval vessels it considered could possibly carry nuclear weapons to visit New Zealand. This clashed with US policy to neither confirm nor deny the presence of nuclear weapons aboard visiting vessels. Consequently, in 1986, the US suspended its security obligation to New Zealand. However, Australia and the US quickly re-affirmed their bilateral relationship.

Today, Australia enjoys bilateral security relationships with both New Zealand and the US under ANZUS. The treaty, while not formally revoked after the US- New Zealand nuclear dispute, no longer fully exists in practice. Nevertheless, a security relationship between the US and New Zealand exists as members of the Five Eyes intelligence community, discussed later in this article.

What does the ANZUS Treaty require of its signatories?

The ANZUS Treaty is somewhat less watertight than some Australians likely believe. Unlike the North Atlantic Treaty that established NATO, which commits its members to collective defence under Article 5, ANZUS provides a significant degree of flexibility.

For example, Article III of the ANZUS Treaty states that the allies will ‘consult together whenever in the opinion of any of them the territorial integrity, political independence or security of any of the Parties is threatened in the Pacific’. The use of the word ‘consult’ suggests that neither side is obliged to commit to military action. It is feasible that in the event of a crisis, Australia (or the US), may choose not to commit military forces. 

Further reducing any sense of obligation, Article IV of the treaty also notes that each ally will meet ‘common danger in accordance with its constitutional processes’. This suggests, for example, that the US Congress may vote not to declare war in a crisis. Similarly, Australian leaders could decide against a military response, even if the US called for one. 

Key Australian decision-makers have highlighted the ambiguity at the heart of ANZUS. In 2004, Foreign Minister Alexander Downer observed that ANZUS would be invoked in the event of an attack on the US or Australian mainland, but not necessarily by military activity elsewhere, and indicated that Australia would not consider itself obligated to assist a US defence of Taiwan. More recently, former Defence Minister Peter Dutton argued it was ‘inconceivable’ that Australia would not fight alongside the US to defend Taiwan, before softening his language by claiming that Australia would decide what is in its best interests if such a scenario occurred.

Future prospects

The reliability of the US alliance has been questioned by some analysts due to 2 unfavourable trends. First, the Trump administration brought into sharp relief the hyper-partisanship of domestic American politics and the wavering commitment of one major party to international alliances. Though President Biden has gone some way to rebuilding trust among US allies, doubts are emerging about US staying power now that the populist, protectionist sentiments that Trump brought into the mainstream seem set to endure.

Secondly, the shifting balance of power in East Asia means that US primacy is no longer guaranteed as China emerges as a peer competitor. Hugh White, a prominent Australian strategic analyst, has argued that this shifting balance of power means that Australia cannot rely on America and needs to prepare to fight alone to defend itself. Another doyen of Australian strategic analysis, Paul Dibb, takes an opposing view, contending that, regardless of who occupies the White House, the alliance will remain the wellspring of Australia security, without which the ADF would not be a credible military force. The Morrison Government appeared to lean towards this view, as demonstrated by the signing of the AUKUS partnership, discussed below.

Bilateral security relationships

Before considering AUKUS, it is worth noting that Australia is also cultivating bilateral security relationships with countries such as Japan, India and South Korea, consequential powers located in the Indo-Pacific that share concerns about China’s strategic trajectory. These growing bilateral ties complement cooperation between the partners in minilateral organisations, such as the Quad, discussed later in this article. However, it is possible that Australia is cultivating these relationships as a hedge, in case US security commitments lose credibility in the future.

As the Department of Foreign Affairs and Trade highlights, Australia has built a broad security relationship with Japan, which it elevated to a Special Strategic Partnership in 2014. The 2 countries hold regular 2+2 meetings between their ministers for defence and foreign affairs. Furthermore, the 2 countries have signed a Reciprocal Access Agreement. As the Australian Institute of International Affairs observes, this is designed to facilitate:

… closer and smoother practical military-to-military cooperation between the Australian Defence Force (ADF) and the Japan Self-Defense Force (JSDF) by legislating sensitive areas, such as access to one another’s military bases and ports, logistical streamlining, and harmonising relevant security protocols. This is designed to facilitate joint military training and exercises on Australian and Japanese territory by cutting some of the existing red tape.

Australian strategic ties with India are also growing, with an Indian analyst, Dhruva Jaishankar, identifying rapid developments since 2014 in the form of military exercises, civil nuclear cooperation, and the establishment of dialogues at the ministerial level. This relationship is widely understood to have been catalysed by the challenge posed by China and it reached new heights in 2020 with the establishment of a Comprehensive Strategic Partnership and Mutual Logistics Support Arrangement designed to promote interoperability between the 2 countries’ armed forces.

Australia also signed a Comprehensive Strategic Partnership with South Korea in 2021, strengthening security cooperation between the 2 countries. They also hold 2+2 meetings between their foreign and defence ministers to facilitate discussion on areas of shared concern. Jada Fraser, a Johns Hopkins analyst, has observed that, as 2 middle-powers, Australia and South Korea have shared interests in maintaining stability in the Indo-Pacific and protecting the rules-based international order. In this context, it is interesting to note that Australia has recently purchased howitzers from a Korean defence firm and may yet buy infantry fighting vehicles from the same company.

Minilateral security relationships


Announced in September 2021, AUKUS is a trilateral security partnership between Australia, the UK and the US. The centrepiece of the partnership is the collaboration between the 3 parties to help Australia acquire a nuclear submarine capability. Achieving this ambition will be an expensive, complex endeavour with the first boat scheduled to be commissioned by the late 2030s, though this timeline is subject to the delays that often bedevil complex military procurement projects.

The AUKUS announcement also articulated other more readily achievable outcomes, including enhanced interoperability between the 3 partners, with efforts focused on cyber capabilities, artificial intelligence (AI), quantum technologies, and additional undersea capabilities. Australia has perhaps seen the first fruits of these endeavours in the announcement of the REDSPICE project, which will expand the Australian Signals Directorate’s cyber capabilities (p. 85) and the announcement that Defence will partner with a firm called Anduril to build an autonomous undersea warfare capability (an uncrewed submarine).

AUKUS has emerged from a confluence of interests between the 3 parties. The Morrison Government, as highlighted above, appeared to determine that it needs to draw even closer to the US, the only country with the strategic weight required to balance the growing power of China. The new Albanese Government appears to be following this line. The US, for its part, is using AUKUS to cement the alliance with Australia, which some American foreign policy officials had viewed as susceptible to ‘flipping’ and leaning towards China. An Australian nuclear force will also, from the allies’ perspective, improve the correlation of forces in the Indo-Pacific in the context of China’s rapidly growing navy. From Britain’s perspective, AUKUS offers opportunities for its defence industry and an opportunity to implement its blueprint for ‘Global Britain’ as a more globally-engaged post-Brexit actor.

All parties will seek to benefit from economies of scale, particularly Australia and the UK, which lack the resources to compete at the cutting edge of emerging technologies such as AI and quantum computing. To put the challenge in context, China spent $378 billion on research and development in 2020, according to CNBC, and in 2021 announced that spending will increase by more than 7% per year between 2021 and 2025.

As for the future of AUKUS, some analysts have suggested that the scope of AUKUS could be widened to include collaboration with other countries concerned about China’s direction. An AUKUS Plus arrangement could include collaboration with states such as Japan, India and South Korea, though this does not seem to be likely in the immediate future. While the former Japanese prime minister, Shinzo Abe, has called upon Japan to work with AUKUS on cybersecurity and artificial intelligence, and Japan’s ambassador to Australia, Shingo Yamagami, has stated his country is willing to contribute to AUKUS projects, both the US and Japan have denied reports that Japan was invited to join the partnership. However, it is possible that the issue of expanding AUKUS will be raised during the span of the 47th Parliament, particularly if tensions with China grow as a consequence of, for example, escalating border conflict with India or increasing tensions with Japan in the East China Sea.

The Five Eyes intelligence community

In addition to AUKUS, Australia, the US and UK are also members of the Five Eyes intelligence community, along with Canada and New Zealand. The community has its origins in the 1946 UKUSA Agreement, which the RAND Corporation describes as ‘an unprecedented intelligence alliance that quickly incorporated Australia, Canada, and New Zealand’. The UKUSA Agreement underpinning the community – referred to interchangeably as a relationship, alliance or partnership by members – is a formal arrangement to share intelligence, including communications, translations, analysis and code breaking information.

The community is based on intimate collaboration and the understanding that intelligence-sharing is a valuable force multiplier that provides significant advantages to each member. The community operated on a global basis during the Cold War to meet the political and military threat posed by the Soviet Union before pivoting to tackle the challenges posed by transnational terrorism and to facilitate the military operations that followed the September 11 attacks.

RAND highlights the complex security environment the community faces today, noting:

… it no longer faces a single predominant threat. The intelligence communities of all five nations must now contend with self-radicalized terrorists at home, master an entire new domain of cyber threats, and remain ahead of Russia and China. And the Five Eyes must do all this while recruiting and retaining the best staff, allaying concerns over civil liberties, and managing the wavering political will for international cooperation.

In recognition of the growing challenges facing the community and the benefits endowed by international cooperation – contestability, a wider pool of expertise and the advantages of scale – some analysts have discussed the possibility of expanding the community to ‘six eyes’ by inviting Japan to join. The British Prime Minister, Boris Johnson, has made supportive remarks, and Japan’s ambassador to Australia has stated that he would ‘like to see this idea become reality in the near future’.

An additional issue that may emerge is the position of New Zealand within the community, with a Canadian Security Intelligence Service report noting that an academic workshop had considered New Zealand particularly vulnerable to Chinese influence, which could risk exposing the Five Eyes network to unauthorised access.

New Zealand appears to be becoming something of an outlier among Five Eyes countries due to its reticence to criticise China, with one academic claiming this lack of unity ‘gives China confidence that its policies of divide and rule, its policies of effectively buying peoples’ and countries’ loyalties through major investment though special trade deals, through guaranteeing access to China’s tourists, China’s dollars, China’s market is working’.

The Quad

As its name suggests, the Quadrilateral Security Dialogue, commonly termed the Quad, consists of 4 members – Australia, the US, Japan and India. As the Council on Foreign Relations highlights, maritime cooperation between these powers began in response to the 2004 Indian Ocean tsunami, but cooperation has widened to embrace a broader agenda, including security, economic and health issues.

The Quad is not a formal alliance and its efforts have waxed and waned in the past. However, from 2016, shared concerns about the challenge that China poses to the US-led order in the Indo-Pacific have encouraged greater cooperation between Quad members. They have conducted military exercises, assisted COVID-19 response efforts, identified a role in addressing vaccine production, climate change and emerging technologies, and seek to help the region develop high-quality infrastructure, offering an alternative to China’s Belt and Road Initiative.

Some commentators have argued that the Quad should be expanded to include other regional powers wary of China’s growing influence. France, which controls significant territory in the Indo-Pacific, is often suggested as a potential member. Some analysts have also recommended British membership, citing the UK’s growing strategic relationship with Japan, interest in maintaining the existing order and existing status as a maritime power in the region.

Five Power Defence Arrangements

Like ANZUS, the 1971 Five Power Defence Arrangements (FPDA) is a legacy of the Cold War. Consisting of Australia, Malaysia, New Zealand, Singapore and the UK, the FPDA commits its members to consult in the case of an attack on Malaysia or Singapore.

As the International Institute for Strategic Studies (IISS) highlights, the FPDA was formed during an era of conflict in Southeast Asia and when Indonesia’s ‘confrontation’ – a small, undeclared war between Indonesia and Malaysia involving troops from Australia, New Zealand and Britain – was a recent memory. The arrangements therefore tied Australia, NZ and the UK to the defence of Singapore and Malaysia.

While it may appear somewhat dated, the IISS argues that the FPDA holds particular significance for Australia, ‘as a sub-treaty recognition that Peninsular Malaysia is tied tangibly to its security and falls within Canberra’s outer defence perimeter’. Australia today maintains a military presence at the Royal Malaysian Air Force’s Base Butterworth.

A number of challenges face the FPDA. A key one is the issue of interoperability, with countries such as New Zealand and Malaysia falling far behind the other partners in terms of military capability, creating what the IISS terms a 2-tier grouping. The FPDA also suffers from a lack of attention, which is typically focused on more high-profile security partnerships. The IISS observes that the inclusion of Malaysia is crucial – if it loses interest in participating, ‘Australia, the UK and New Zealand would lose significant access for their armed forces in Southeast Asia’.

Finally, cooperation with other countries is complicated by conservatism – Malaysia and Singapore fear expansion would dilute the focus on defending them, while Australia, New Zealand and Britain fear it would dilute their importance as security providers.

As the East Asia Forum observes, Southeast Asia’s strategic circumstances have changed significantly since the FPDA was established, with US-China competition intensifying across the region. As China’s increasing assertiveness brings it into conflict with Malaysia’s South China Sea claims and the risk of war rises in the context of great-power competition, the little-known FPDA may gain increasing prominence.

Global security relationships – Australia’s relationship with NATO

Though Australia is not a NATO member, its ties to the organisation have grown as a result of ADF deployments to Afghanistan under the NATO-led International Security Assistance Force. The 2 parties have signed a number of agreements to institutionalise their relationship across a variety of themes, including defence capacity-building, crisis management and Women, Peace and Security. Australia is one of NATO’s Enhanced Opportunity Partners, a program that aims to maintain and deepen cooperation between partners that have made significant contributions to NATO-led operations and missions. This status includes enhanced access to interoperability programs and exercises, and more sharing of information, including lessons learned, which will help to improve the effectiveness of the ADF.

Most recently, in April 2022, Foreign Minister Marise Payne attended a meeting of NATO foreign affairs ministers in Brussels to discuss the coordinated response to Russia’s invasion of Ukraine. Furthermore, Minister Payne also announced that Australia will partner with the NATO Strategic Communications Centre of Excellence to help strengthen NATOs capacity to address hybrid threats and to counter disinformation. As part of this endeavour, Australia will initially contribute to research conducted at the centre through a seconded Australian official. Australia has also begun the process of becoming a longer-term contributing partner of the centre.

Further reading

Michael Fullilove, ‘America and Australia are Back on the Same Page’, Lowy Institute, 11 February 2022.

Hugh White, ‘Australia Must Plan to Defend Itself Alone’, The Strategist (blog), 13 January 2020.

Emma Shortis, ‘The ANZUS Treaty Does Not Make Australia Safer. Rather, it Fuels a Fear of Perpetual Military Threat’, The Conversation, 1 September 2021.

Peter Dean, ‘ANZUS Pivot Points Reappraising “The Alliance” for a New Strategic Age’, Black Swan strategy paper, (Perth: UWA Defence & Security Institute, March 2022).

Alexander L. Vuving, ‘AUKUS is a Short-Term Mess but a Long-Term Win for Australia’Foreign Policy, online, 11 October 2021. 


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