U.S.-Australia Alliance Force Posture, Policy, and Planning: Toward a More Deliberate Incrementalism

Alliance Future: Rewiring Australia and the United States

The Carnegie Asia Program’s “Alliance Future” project aims to ensure that Canberra and Washington are working to operationalize and integrate their alliance in new ways. The project explores how to undertake difficult reforms, forge new modes of cooperation, harmonize outdated regulations, better align national strategies, address sovereignty concerns and risk thresholds, and ultimately reform the alliance for a more competitive era.

Introduction

In Article II of the Australia, New Zealand, and United States (ANZUS) Security Treaty—which is nearly identical to Article III of the founding document of the North Atlantic Treaty Organization (NATO)¹—Australia and the United States pledged that “in order more effectively to achieve the objective of this Treaty the Parties separately and jointly by means of continuous and effective self-help and mutual aid will maintain and develop their individual and collective capacity to resist armed attack.”² Since 2020, Australia and the United States have announced a number of force posture initiatives that, at first glance, seem to increase the importance of the “collective” rather than “individual” elements of this pledge. Yet, in light of the low level of prior force posture cooperation, changes over the years since have been significant more for their novelty than for their overall effect on the U.S. force posture in the Indo-Pacific or Australia’s national defense effort.

A confluence of factors has made Australia less reluctant to increase the scope for U.S. forces to operate in and from Australian territory, but there is no sign that this will bring U.S. and Australian national defense postures into closer alignment. Indeed, statements from the Australia-United States Ministerial Consultations (AUSMIN)—between the U.S. secretaries of state and defense and Australian ministers for foreign affairs and defense—in 2023 and 2024 have actually dropped references to multilateral deterrence that had been included from 2020 to 2022. Australia’s own reconsideration of its national force structure and posture in the 2023 Defence Strategic Review (DSR) and 2024 National Defence Strategy (NDS) continues to conceive of Australian posture and defense strategy on purely national lines.

To maintain the momentum of practical cooperation since 2020, Australian and U.S. policymakers should seek pragmatic steps that evolve cooperation with, rather than against, the grain of Australia’s current policy realities. In particular, they should focus on cooperation that reflects overlapping national interests in operations closer to Australia, and on strengthening deterrence by facilitating horizontal rather than vertical escalation.

The Legacy of History: Allies in Permanent Separation

The basis of the U.S.-Australia alliance is the ANZUS Treaty, signed in 1952 by the United States, Australia, and New Zealand. (U.S. commitments to New Zealand would later be suspended by the United States in 1986 over a nuclear dispute, so that for Australia the treaty is now the basis for two bilateral alliances.) In the late 1950s and early 1960s, the short-lived and ill-fated Southeast Asian Treaty Organization (SEATO) temporarily complemented ANZUS, but the institutions it created were carefully limited to its own, separate treaty commitments and relationships. Instead, the 1952 Radford-Collins Agreement between the U.S. and Australian navies embodied an approach of minimal coordination, based on geographic division into different zones of responsibility³—rather than integration as in NATO (or the U.S.-South Korea alliance) or allocation of different roles in the same geographic area (as in the U.S.-Japan alliance). Politically, Australia’s post-Vietnam War defense identity was closely linked to the concept of defense “self-reliance,” which meant that Australia sought to be able to defend itself against regional threats (in particular, Indonesia) without having to rely on assistance from U.S. combat forces.⁴

This is not to say that the Australian and U.S. defense and intelligence communities did not develop close ties. Of particular importance are the Joint Facilities in Australia (including satellite and submarine communications) and joint military operations after the September 11, 2001, attacks in various conflicts across the Middle East. Australia and the United States continued to coordinate maritime surveillance in Southeast Asia, but since the end of the Vietnam War, the focus of their defense preparations lay on different threats in different parts of the Indo-Pacific area. They therefore never developed structures for, or even habits of, coordinating regional force posture (let alone force structure).

In 2012, a new era seemed to dawn as Australia and the United States embarked on the Force Posture Initiative (FPI), the centerpiece—and ostensibly only the first component—of which were rotational training deployments of U.S. marines to Australia’s Northern Territory. However, the initiative is best understood as a political gesture of support for then U.S. president Barack Obama’s “pivot to Asia,” rather than a reassessment of Australia’s own strategic policy and approach to the alliance. By emphasizing Australia’s “full knowledge and concurrence” regarding U.S. operations on Australian territory, a 2012 statement to parliament placed FPI cooperation firmly into the context of the long-standing cooperation on the Joint Facilities.⁵ Australia’s subsequent 2013 Defence White Paper showed no significant reassessment of the role of the alliance or the U.S. presence in Australia’s approach to regional security.⁶

Despite the perception of a close alliance, Australia and the United States must clear higher hurdles than in other alliances to embark on closer force posture integration. These include the lack of relevant policy legacy and traditions, Australian concerns about entrapment and sovereignty implications, the lack of a shared sense of threat and urgency (at least within the wider system of government in Canberra), and traditionally limited U.S. policy attention to the management of the Australian alliance.⁷

Not surprisingly, even though the allies had flagged further naval and air cooperation when announcing the FPI in 2012, little of substance eventuated beyond cooperation on new space surveillance radars in Northern Australia—and long negotiations on cost-sharing. When U.S. officials floated the possibility of deploying U.S. bombers in 2015—or new intermediate-range missiles in 2019—Australian ministers were quick to publicly squash such suggestions.⁸ The conservative Liberal-National Coalition’s 2016 Defence White Paper emphasized upholding global “rules-based order” as the central task for the Australian Defence Force (ADF), deliberately eschewing the traditional policy prioritization of developments in Australia’s own region. In short, nothing about Australian defense policy in the years following the FPI in 2012 suggested that Australia and the United States had moved to a changed understanding of the nature of their alliance, a shared recognition of the threat coming from China, a greater sense of the joint military steps necessary to meet this threat, or more urgency in doing so.

Progress Since 2020: Cooperation Without Alignment

In 2019, the AUSMIN communiqué did not even mention deterrence, nor did it reference new developments on force posture cooperation.⁹ This all changed in 2020, which emerged as a watershed year for greater progress on force posture cooperation as well as political commitment to multilateral deterrence. The allies announced work on a classified “Statement of Principles on Alliance Defense Cooperation and Force Posture Priorities in the Indo-Pacific,” with the aim to “deter coercive acts and the use of force.”¹⁰ Initial signs of this increased cooperation included Australian-led contracts for infrastructure to host four tanker aircraft at its Tindal air base south of Darwin,¹¹ as well as U.S. investment in military fuel storage in the port of Darwin.¹² In 2021—in addition to the announcement of the Australia-UK-U.S. security agreement (AUKUS)—Australia and the United States also agreed to create “a combined logistics, sustainment, and maintenance enterprise to support high‑end warfighting and combined military operations in the region.”¹³ A subsequent agreement in 2022 expanded the Australian air base at Tindal to enable it to host six B-52 bombers,¹⁴ and both countries announced plans for further joint enhancement of Australian bases, fuel, and ordnance storage sites to enable operations by U.S. air and land forces.¹⁵ In 2023, the allies announced that the United States would establish Submarine Rotational Force – West, with up to four Virginia-class submarines stationed in Perth from 2027 as part of AUKUS.¹⁶ The same year, they also announced regular rotations of U.S. Army watercraft to Australia, the scoping of upgrades to Royal Australian Air Force (RAAF) Bases Curtin and Scherger, the establishment of a guided weapons production and maintenance capability, plans to produce guided multiple launch rocket systems, and the maintenance, repair, overhaul, and upgrade of Mk-48 torpedoes and SM-2 missiles in Australia.¹⁷

Yet this seemingly rapid progress, at least compared to the period from 2012 to 2019, is not due to a fundamental reassessment of the alliance and how it relates to Australia’s own defense policy, structure, and posture. Rather, it is best explained by the erosion of the political, policy, institutional, and international barriers and concerns that had led Australia to be reluctant to agree to greater cooperation in earlier years. One key development was Chinese economic and political coercion of Australia. This significantly shifted the public’s perception of—and policy debate on—China as a threat to Australia, and undercut the argument that Australia’s economic relationship with China would benefit from, or even require, political distance from the United States.¹⁸ The 2020 Defence Strategic Update, produced by then prime minister Scott Morrison’s government, provided greater focus—and a greater sense of urgency—on conflict with China in national defense policy settings, and it placed deterrence at the core of Australia’s national defense discourse.¹⁹ Since then, the Australian Department of Defence has been slowly developing institutional processes and expertise in assessing the implications of major war that might see U.S. forces operating from Australia. This is reinforced by the 2023 DSR, which recommended a so-called net assessment–based planning model and for the government to endorse defense planning scenarios. In Washington, AUKUS certainly increased the priority of Australia-related issues for busy Pentagon executives. And while Australia has always been sensitive to regional perceptions, the participation of Australian tanks transported from Darwin on a U.S. vessel to exercises in Indonesia,²⁰ as well as the first-ever visit of a U.S. B-52 bomber to Indonesia,²¹ seem to signal Jakarta’s growing comfort with increased U.S.-Australia force posture cooperation.

However, despite being more receptive to an increased U.S. presence in Australia, major defense policy statements by the governments of both Morrisson and his successor, Prime Minister Anthony Albanese, have continued to place Australian security in a local context. Australia’s own concept of security is based on self-reliant operations for local “deterrence by denial” and its own defense, rather than to ensure the success of multilateral deterrence.²² Seemingly major new capability decisions do not fundamentally change this predominantly local outlook. Despite the political significance of the AUKUS partnership, the practical reality is that shifting to nuclear-powered submarines (SSNs) will mostly preserve Australia’s ability to operate the same way it always has with its fleet of conventionally powered submarines in more benign times. Hence, it represents continuity rather than change in Australia’s naval ambitions.²³ And while the acquisition or deployment of Tomahawk (or other long-range) missiles is of strategic significance in Europe, Japan, and South Korea, because it opens new escalation options against an adversary’s homelands, the same is not true for Australia. There, the decision to acquire these systems is part of a broader realization that the ADF’s guided missile arsenal was—in range and capability—inadequate for the geographic expanses of Australia’s northern approaches.

The 2023 DSR and 2024 NDS are important reality checks on Australia’s ambitions for—and, indeed, the limited importance of—force posture integration in Australia’s national policy. Both place the concept of “denial” in the country’s northern approaches at the core of Australian defense planning. In many ways, this is an updated and more proactive version of Australia’s posture in its seminal 1987 Defence White Paper.²⁴ In conjunction with its increased willingness to host U.S. long-range air and submarine forces, as well as U.S. Army watercraft, Australia’s national-level force structure and posture development could be seen as complementary to that of the United States—an Australian version of the old U.S.-Japan “shield and sword” division of labor.²⁵

Yet neither the 2023 DSR nor the 2024 NDS describes the intent or direction of Australia’s defense policy in this way. Instead, the (rather vague) concept of deterrence is linked to the (equally vague) concept of denial,²⁶ and neither discusses it in meaningful ways as part of multilateral- or alliance-level deterrence of conflict in the wider Indo-Pacific. That Australia would work with “the US and other key partners to make a credible contribution to a favourable regional strategic balance” and that it would “[deepen] defence engagement to enhance and maintain the capability to make greater contributions to collective deterrence” is all the 2024 NDS has to offer on that matter.²⁷ Indeed, where the NDS actually specifies the basic security threat to Australia, it consistently refers to “strategic competition” between the United States and China,²⁸ rather than a possible Chinese effort to deter or defeat the United States and its allies in an attempt to establish regional hegemony. And in a return to language similar to that used before 2020, the 2023 and 2024 AUSMIN communiqués announced additional practical force posture cooperation without making a link between that cooperation and deterrence or countering coercion.²⁹

It is not surprising, then, that neither the 2023 DSR nor the 2024 NDS reference alliance “roles and missions” as something that should be taken into account in Australian defense planning. Remarkably, Australian strategic guidance today thus has less to say on how possible commitments to broader Indo-Pacific security should factor into Australian force structure and posture than, for example, the 2000 Defence White Paper, which laid out broad guidance on how forces should be designed to meet Australian strategic interests through coalition operations in the South West Pacific, Southeast Asia, and globally.³⁰ Of course, that approach reflected a time when Australia could think of contributions to regional conflicts as a contingency quite separate from the defense of its own territory. And there may well be U.S.-Australia agreements on cooperation that still remain classified. But neither caveat changes the fact that the vast majority of Australian staff officers, defense planners, and public servants—who must make myriad practical decisions that collectively shape Australian force posture and structure outcomes—do so with less of an explicit policy framework on how Australia’s national objectives align with alliance cooperation than their predecessors had two decades ago.

Despite the awakening of Australian defense policy to the possibility of major war with China,³¹ Australia’s own policy does not articulate a strategic concept for force posture cooperation, let alone a shared concept for escalation or the management of escalation stemming from the role of U.S. long-range forces operating out of Australia.³² Of note, the practical progress in recent years was almost contained to areas where Australia’s interests for its own local defense overlapped with U.S. interests in long-range operations. The need to develop runways and fuel and armament storage at Australia’s northern bases, for example, has been long recognized in Australian policy.³³ The increased training and industrial opportunities that come from hosting U.S. SSNs in Australia are key elements in the so-called optimal pathway for Australia’s acquisition of its own SSNs. The reorganization of Australia’s army for littoral operations in the South Pacific aligns its own practical challenges more closely with those of the U.S. Marine Corps and U.S. Army in the Indo-Pacific.³⁴ And the importance of Australia creating armaments production capabilities that are less reliant on overseas supply mirrors U.S. interests in broadening and expanding production capacities globally.

Hence, while the U.S.-Australia alliance may be drifting toward closer force posture cooperation, it remains adrift insofar as practical cooperation is driven by largely coincidental overlap of national interests, rather than by a shared understanding of the practical needs for deterrence and escalation management—let alone a joint concept for major war. Indeed, progress may already be slowing. And increased force posture cooperation has not been seriously tested by the need to manage either a regional crisis or a political crisis—such as a radically changed approach to the region or to allied burden-sharing if former president Donald Trump returns to the White House—that may well arise, if not between the allies then in terms of domestic Australian politics.

Toward a More Deliberate Model of Incrementalism

The manner of practical cooperation in every alliance reflects its history and allies’ strategic cultures and traditions. NATO collaboration grew over time among allies that deliberately defined themselves as a political-military community. Cooperation in the U.S.-Japan alliance reflects Tokyo’s strong legalistic approach to practical cooperation. And the U.S.–South Korea alliance is still trying to shed the last vestiges of an era when Seoul was almost without any say in its own defense. In comparison, the U.S.-Australia alliance is largely a blank slate. The United States and Australia are unlikely to ever hold an equivalent to a NATO summit, where, at least every few years, decisions are made on strategy, force posture, and structure that can deliberately reshape the political and practical direction of alliance cooperation.³⁵

Indeed, unlike NATO or the U.S-Japan alliance, Australia and the United States never refer to their joint decisions or posture as being of “the Alliance.”³⁶ The idea that the U.S.-Australia alliance might express a collective identity or community committed to joint action—and, hence, one that should developed shared strategic concepts, plans, and understandings as a basis for closer integration—remains alien to Canberra’s approach to cooperation with Washington. Instead, Australia’s political and strategic culture has created a narrative on local defense self-reliance, and the evolution of alliance cooperation on the Joint Facilities toward full knowledge and concurrence between nominally equal partners—as part of the country’s long maturation from a colony into an independent nation.

Unfortunately, however, alliance cooperation driven by bottom-up, practical cooperation has a tendency to overstep political bounds, leading to tensions if such boundaries are then reestablished. For example, after U.S. bombers returned to the UK in 1946, difficult negotiations regarding U.S. operations from the UK were a sore point in U.S.-UK relations throughout the 1950s.³⁷ Norwegian intelligence’s cooperation with the CIA on the ill-fated U-2 flight of Gary Powers in 1960 reinforced the Norwegian government’s determination to impose stricter political control on the activities of U.S. forces from Norway.³⁸ And in 2013, the frigate HMAS Sydney was temporarily embedded in the U.S. Seventh Fleet³⁹—a decision that, according to Canberra lore, was initiated by both navies and blindsided Canberra policymakers. Joint naval patrols or operations in the region, despite their shared interest in maintaining a national regional presence, have remained a notable gap in U.S.-Australia cooperation ever since. More recently, scholar Ashley Townshend observed that the extent of practical cooperation between the RAAF and visiting U.S. bomber task forces may well already outpace the political intent behind incremental steps that officials agreed to.⁴⁰

If Australia and the United States are to avoid a similar crisis and maintain the limited momentum since 2020, they need to find a politically feasible framework to progress and guide the deepening of their force posture cooperation. Discussions of “roles and missions” run against the grain of Australia’s own national guidance and defense policy identity. And seeking to develop joint strategy and agreed-upon plans for top-down guidance of practical cooperation, based on a politically difficult presumption of joint action, would likely bring to the fore political ambiguity about Australia’s integration with preparations for U.S. vertical escalation.

Instead, both allies should consider practical cooperation in areas that reflect Australia’s preparations for major war in its immediate neighborhood; that support multilateral deterrence by facilitating politically palatable horizontal, rather than vertical, escalation; and that help move force posture cooperation from enabling U.S. activities on Australian territory toward greater overall alignment of both countries’ defense preparations. With this in mind, both allies should consider the following five directions to provide greater focus, purpose, and direction to force posture and structure cooperation.

 Try to Say a Little More Each Time

The United States and its Indo-Pacific allies have been grappling with how to best balance a rising China for years. Recently, they have often embraced the buzzy concept of integrated deterrence. Yet they have not coalesced on a shared concept of deterrence and escalation that would direct how they think about the coherence and complementarity of their respective national force structure and posture developments. Australia and the United States first started to draw an explicit link between multilateral deterrence and their force posture initiatives in the AUSMIN communiqué of 2020, but they subsequently dropped that reference in 2023 and 2024. Despite the seemingly ever-increasing length of these communiqués, they continue to contain little that would indicate a shared understanding, or even a sustained conversation, about the foundations of strategic stability in the Indo-Pacific.

Such understandings do not arise easily. There is little appetite in Canberra to embark on the development of a document akin to NATO’s Strategic Concept or the U.S.-Japan defense guidelines, which would only serve to foreground fundamental disagreements, both between the allies and within Canberra itself, on deterrence and alliance strategy. But one way for both allies to work toward narrowing differences and identifying shared tenets is by aiming to say a little more each time their ministers meet at their regular summits. Over time, restating the enduring principles that relate to deterrence and strategic stability can establish a canon on which future work and practical implementation can be based. NATO, for example, has developed a set of longstanding statements about the nuclear aspects of its deterrence. “The strategic nuclear forces of the Alliance, particularly those of the United States, are the supreme guarantee of the security of the Alliance” dates to the Cold War; “Missile defence can complement the role of nuclear weapons in deterrence; it cannot substitute them” dates to the 2012 Defence and Deterrence Posture Review; and that UK and French nuclear forces contribute to deterrence through “separate centres of decision-making . . . by complicating the calculations of potential adversaries” dates to the Ottawa Summit of 1974. All of these principles are again included verbatim in NATO’s 2023 communiqué following the summit in Vilnius.⁴¹

For the United States and Australia, such an approach should focus on issues that both allies can agree on, that avoid traditionally sensitive questions (such as the geographic scope of the ANZUS treaty commitment), and that provide more explicit strategic rationale for ongoing cooperation. For example, a general statement such as “The ability of U.S. forces to reinforce the western Pacific is an important element of crisis management, strategic stability, and allied security” might be seen as stating the obvious, but it would be a useful opportunity to engage political decisionmakers and the Australian public on the strategic benefit of force posture cooperation. Given that Australian governments have, for many years, acknowledged the importance of U.S. extended deterrence in deterring nuclear attacks on Australia, the allies might consider regular statements such as “As long as nuclear weapons exist, U.S. nuclear forces remain an important element of strategic stability in the Indo-Pacific.” This would provide a basis for both public and policy discussions on Australia’s possible role, without prejudging that there should be any role at all beyond the operation of Joint Facilities.⁴² And though Australian defense policy statements have been largely silent on the limits of self-reliance, a statement such as “While Australia’s self-reliant defense posture is an important contribution to allied burden-sharing, possible adversaries should not doubt U.S. ability and willingness to support its allies’ defense” would mirror language used by Australia in the past,⁴³ while opening up the policy space for discussions of closer U.S.-Australia operational cooperation on continental defense.

Focus on Overlapping Operational Needs and Challenges

Although Australia’s defense policy as laid out in the DSR and NDS is largely silent on how it relates to U.S. military strategy in the Indo-Pacific, an ADF that is prepared to defend Australia is broadly consistent with U.S. aims. Australia’s main value to the United States in case of a major war is as a secure base area for long-range operations into Southeast Asia and southern China.⁴⁴ But Australia is hardly the only U.S. ally where the question of practically and politically balancing local defense with supporting offensive operations against a possible adversary’s territory is extremely challenging policy waters to navigate.⁴⁵

While the agreement to prepare hardstands for U.S. B-52 bombers at RAAF Base Tindal attracted relatively little political attention in Australia, that is likely because AUKUS has become the focal point for public debate over alliance cooperation instead. In contrast, joint approaches to developing basic infrastructure at Australia’s chain of so-called bare bases in its remote North or the combined logistics, sustainment, and maintenance enterprise are less likely to run into political challenges. These plans are consistent with what Australia has identified as operational priorities for the defense of Australia itself—and Australian policy never interpreted defense self-reliance to mean strategic autonomy. That said, it is notable that the 2024 NDS does not include a statement on Australia’s aim to defend itself without relying on U.S. combat forces, which existed in varying formulations in all Defence White Papers from 1976 to 2013.⁴⁶ In reality, the ADF is almost certainly too small for the likely demands of defending the continent, even against the limited air, maritime, or special forces threats that China might project from the South China Sea or possible future regional bases against the Australian homeland and vital shipping routes.⁴⁷

With the presence of Chinese SSNs in the Indian and Pacific Oceans, the threat of cruise missiles and to shipping extends all around the Australian coastline, including the major population centers and defense facilities in the southeast and in Canberra. These are difficult and uncomfortable challenges for Australia, but would be a useful focal point for discussions on how to better align U.S. and Australian force posture for major conflict. This is not to say that Washington could, would, or should directly make up for inadequacies in yet another ally’s defense preparations. But the United States has a lot to benefit from Australia realizing and addressing its limitations, and it has relevant experience that could be helpful.

The defense of the U.S. West Coast and Australia’s east and southeast present very similar challenges in terms of their geographic distance from adversary bases but increasing vulnerability to cruise missiles launched from SSNs or long-range bombers. While Australia is a similar size to the continental United States, the RAAF’s roughly one hundred fast jets lacks the home-defense squadrons that the United States maintains through its National Guard.⁴⁸ Australia’s planned six NASAMS fire units will likely not just be inadequate for the number of facilities that need protection,⁴⁹ but also are ostensibly being acquired to defend forward-based land forces rather than, for example, irreplaceable submarine and naval bases in Sydney and Perth. Joint examination of these issues, including drawing on the analytical work that underpins the U.S. homeland cruise missile defense program,⁵⁰ could identify additional specific investments or preparations that would benefit both sides’ wider operational objectives.

A second focal point arises from the decision to create a combined logistics, sustainment, and maintenance enterprise, though which Australia and the United States have already taken the first steps toward the development of a wartime host nation support (WHNS) model for the alliance. The practical implementation of WHNS often reflects the broader characteristics of the respective alliance. NATO integration, for example, led to the creation of German logistics units equipped to service American equipment to support the flow of U.S. reinforcements to West Germany during the Cold War;⁵¹ WHNS in South Korea to this day includes the Korean Service Corps, a U.S. Army logistics battalion staffed with personnel of locally recruited South Korean nationals.⁵² Australia may balk at the suggestion of creating units to serve other countries’ forces, but both countries should consider the operational and political benefits. Such an arrangement may also help with public support, insofar as it would give Canberra both direct and indirect influence on the operation of U.S. forces from Australia. Public consultation in Australia certainly suggests that there is significant support for closer integration within the alliance, if concerns about Australian sovereignty are clearly addressed.⁵³

Third, the United States and Australia should also examine the overlap of their respective strategic and operational objectives in the South Pacific. For Australia, preparing for littoral warfare in the islands to its northeast has become a central focus since the 2023 DSR. In a departure from its previous emphasis on stabilization operations, Australian policy now reflects the need to deal with the possibility of a Chinese military presence or projection into its immediate neighborhood—concerns that were heightened by the close relationship between China and Vanuatu under former prime minister Manasseh Sogavare.⁵⁴ Direct confrontation between Australia and China in the region could arise from a range of scenarios short of major war, such as Chinese gray-zone challenges to Australian forces supporting Pacific fisheries protection. Ethnic Chinese communities in the region have repeatedly been targeted when law and order broke down (for example, in the Solomon Islands in 2006,⁵⁵ 2019,⁵⁶ and 202⁵⁷), where the future deployment of Australian and other regional police and military forces in support of local authorities could raise the specter of a competing intervention by the People’s Liberation Army. 

In major war, the southwest Pacific is significant for its geographic position along key sea lines of communication that would support the U.S. war effort, notably the lines between Hawaii and Townsville (where the great circle route passes through the Solomon Islands) and Townsville to Manus (and on to Guam or Palau), which passes east of the Papua New Guinea mainland. As in World War II, North Queensland would likely become the key staging area for U.S. operations from Australia, which is reflected in plans to move the combined logistics, sustainment, and maintenance enterprise from its initial location in Victoria to a future “Logistics Support Area” in Queensland.⁵⁸

U.S. convoys passing through the southwest Pacific would need protection against overt and covert Chinese lodgments in the islands. Australia would have an interest in playing a major role in this, not least because U.S. rules of engagement may well be more tolerant of collateral damage to South Pacific nations and their local shipping than Australia would be comfortable with. Hence, examining the relationship between U.S. plans and concepts for strategic sea transport and force protection and Australia’s increased focus on littoral operations in the same region would be a worthwhile area for joint planning and force posture cooperation. As convoys would also require protection against Chinese SSNs further into the central Pacific, there is scope for including New Zealand and France in broader discussions as well.

Facilitate Europe’s Participation in Multilateral Deterrence

New Zealand and France, however, are just some of the third partners that are relevant to the broader deterrence aims of U.S.-Australia force posture cooperation. At the 2022 AUSMIN summit, Australia and the United States invited Japan to participate in aspects of their force posture cooperation.⁵⁹ But while this was politically significant toward cementing the trilateral Australia-U.S.-Japan relationship, operating from Australia is realistically more relevant to Japan for training opportunities than in actual contingencies.

European countries, on the other hand, are also growing more concerned about the implications of the Indo-Pacific on their own security, and increasingly willing to signal this through regional deployments. In 2024, European Air Transport Command, which coordinates strategic lift and tanker assets across most European Union (EU) member states, supported the concurrent deployment of fifty European fighter aircraft and helicopters to exercises across the Indo-Pacific.⁶⁰ Notably, aircraft from Spain, Italy, France, Germany, and the UK, as well as the Italian aircraft carrier Cavour, participated in the 2024 iteration of Exercise Pitch Black in Darwin.⁶¹ While Europe’s military significance in the Indo-Pacific remains limited, it has potential to contribute to multilateral deterrence through its economic importance to China—and increasingly through the revival of its defense industrial base, which would be of particular consequence in a protracted conflict.

While the strategic significance of U.S.-Australia force posture cooperation is often seen primarily though the extent to which it supports deterrence through possible vertical escalation, there are also important benefits from supporting threats of horizontal escalation. European countries signaling their concerns through deployments to the Indo-Pacific is valuable to the United States, Australia, and regional stability more broadly, as it makes Beijing less likely to assume that it could limit the economic costs of precipitating a crisis or that it could politically isolate the United States from its allies to the point where they might withhold practical support through access to their defense industry or by backfilling other U.S. commitments. In a context where Australia’s government may be inclined toward caution and limited commitment, being part of a broader international coalition signaling its concern about possible Chinese aggression could ease the way for Canberra to action bilateral U.S.-Australia cooperation.

The signaling value of European deployments would thus be of greatest value in an actual crisis, which would arise at short notice if China made visible preparations for a major operation against Taiwan.⁶² There are, however, not many destinations to which European nations could send forces in such a crisis to signal their concern. In political terms, they would likely seek control over the decision to becoming actively engaged; in practical terms, ramp space in Japan, Hawaii, or Guam would mostly be taken by U.S. forces. Politically and operationally, Australia is thus a highly plausible and mutually beneficial destination for such deployments. In a crisis situation, European deployments would help shore up Australia’s own commitment, complicate Chinese calculations, and—if it came to war—even relatively small numbers of European fighter aircraft could contribute to the defense of northern Australia.

To date, European naval and air deployments to the Indo-Pacific have typically been planned long in advance, and conducted with numerous engagement stops along the way. In a crisis, the creation of an air tanker bridge between Europe and Australia that relies solely on European, Australian, and U.S. air bases and tanker aircraft would be important for the rapid movement of not just European but also European-based U.S. fighter and strategic transport aircraft into the Indo-Pacific. As a first step toward leveraging their own cooperation to further broaden multilateral deterrence, the United States and Australia should engage their EU partners (as represented in the European Air Transport Command) and the UK to test the implementation of such a transcontinental air bridge, possibly as part of the next iteration of Exercise Pitch Black.

Consider the Benefits of UK Involvement in Force Posture Cooperation

Given its role as a major European military power, its national commitments in the region (including the Five Power Defence Arrangements between Australia, Malaysia, New Zealand, Singapore, and the UK), and its air bases (especially in Cyprus and Diego Garcia), the UK would be a key partner in leveraging U.S.-Australia cooperation into broader coordination with like-minded European countries. But through its involvement in Submarine Rotational Force – West as part of AUKUS, the UK is also already a direct part of U.S.-Australia force posture cooperation. Australia and the United States should thus consider the broader benefits of involving the UK as a partner with unique contributions to offer.

One, often underappreciated, benefit of including the UK in AUKUS is that it has significant experience with the creation of multinational integrated military capability, including the kind of mixed crewing envisaged as part of the AUKUS optimal pathway. Such experience does not always transfer easily within the U.S. military and policy system and its relatively separate Euro-Atlantic and Indo-Pacific policy communities. But it would be especially useful to Australia, given its own limited experience with force integration in peacetime. In particular, this includes U.S.-UK carrier integration⁶³ through which British pilots have operated off U.S. carriers and U.S. Marine Corps F-35s have been integrated with HMS Queen Elizabeth to enable the UK to retain essential capabilities after it decommissioned old carriers⁶⁴—as well as multinational formations including NATO’s Standing Naval Forces and the UK-led Joint Expeditionary Force.

While British deployments to Australia in a crisis would be much smaller than those from the United States, involving the UK in, for example, discussions about the combined logistics, sustainment, and maintenance enterprise would enable deeper consideration of how to support and facilitate the deployment of other countries’ forces. From a purely Australian perspective, a greater understanding of the UK’s decades-long and seemingly quite complex experience with U.S. nuclear and conventional bombers operating from its territory would also be useful in developing political and policy mechanisms to facilitate such deployments in Australia. Off the record, senior UK officials have described arrangements that give the UK a right of veto over U.S. operations from British bases.⁶⁵ The UK did, for example, impose conditions on U.S. operations from British bases during the 1973 Yom Kippur War, which led the United States to eschew their use.⁶⁶ But while former UK prime minister Margaret Thatcher is quoted as saying that “under the Churchill-Truman arrangements, there are no circumstances in which American aircraft based in this country may be used without our consent in military operations planned by the United States,” declassified records do not show any U.S. agreement to binding limits on the use of UK bases for nuclear operations in wartime.⁶⁷

Develop Graduated Response Plans for the Alliance

Since the time of SEATO, which is now beyond living memory, Australia and the United States have had no experience of developing politically endorsed, alliance-level operational plans for future contingencies. While it is perhaps natural for academic and policy debates to gravitate toward the highest level of escalation—including what role U.S. long-range air strikes from Australia against the Chinese mainland may play at the conventional-nuclear threshold⁶⁸—that is not a politically useful starting point to commence such planning in practice. Instead, Australia and the United States should examine the example of NATO’s graduated response plans (GRPs) as a model for deepening joint planning in the alliance.

The GRPs were created after Russia’s invasion of Crimea in 2014. Before that point, there had been no political consensus in NATO on the need for operational plans to reinforce allies on the Eastern flank.⁶⁹ In 2014, NATO agreed on the need to plan for the reinforcement of allies—up to the point where hostilities commenced, as there was not yet political agreement on alliance strategy during such a conflict.⁷⁰ The GRPs identified what reinforcements might be necessary given the geographic and strategic situations in different parts of the alliance, the logistics of how they could be deployed, the political and military decision points and their timing, and what authorities alliance commanders should assume over national forces as a crisis progressed.⁷¹ Political consensus on the need for actual defense plans only arose after Russia’s full invasion of Ukraine in 2022,⁷² but the GRPs enabled NATO to quickly activate tens of thousands of personnel to support its eastern member states.

The development of a U.S.-Australia GRP would thus sidestep politically difficult questions about the overall aims and conduct of a conflict with China, and instead address a whole host of practical questions that would arise well in advance of the outbreak of war. For a start, the development of joint operational plans at the alliance level, in the absence of standing alliance commands, would itself be useful to develop political-military mechanisms in the alliance. By identifying decision points and their operational and political significance, the development of the GRP would help address concerns that closer alliance cooperation would be incompatible with the ability of Australia to make sovereign decisions in a crisis. And the development of the plans would help surface differences or draw attention to issues that would be most inconvenient to first face in an actual crisis. These questions include: What first-mover advantage might there be for deploying forces in a littoral context? What would be the role of and what would happen to forward deployed forces—for example, in the South China Sea—as a crisis develops? When and where should allied submarines surge deployments closer to the conflict zone? Would there be a need to reinforce the Christmas and Cocos Islands, which currently do not have a permanent garrison? At what point might the allies consider deploying naval mines before the outbreak of hostilities? What is the signaling value of deploying U.S. long-range bombers? And does it matter whether these bombers would be nuclear capable or not (a question of interpretation that does not seem to have a clear answer in current U.S. policy or practice)?

By developing the GRP, Australia and the United States would also have to address how their national command-and-control (C2) arrangements would relate to each other. So far, public discussion has mostly focused on the extent to which RAAF assets would be used to support the ingress and egress of U.S. long-range bombers to and from Australia in the context of major war. The example of Norway during the Cold War, however, demonstrates that C2 at the intersection of major strategic commands can also raise very significant challenges in a naval context. These included reconciling the U.S. Marine Corps’ geographically expansive doctrinal approach to providing organic air defense for its reinforcements to northern Norway with local air defense arrangements, and the risk of naval forces straying into coastal defense zones under a different local command.⁷³ Similar challenges would likely arise as U.S. convoys passed through Australian land and naval deployment zones in the southwest Pacific, where even Australia’s own national plans for joint C2 during such operations remain murky at best.

The GRP should be politically endorsed by both allies and facilitated by table-top exercises with actual decisionmakers, which, in turn, would help improve their understanding of the operational and strategic demands of common deterrence and defense. This could build on the political endorsement of ADF planning scenarios introduced in the 2023 DSR. Major exercises—Talisman Sabre in particular—should then start to reflect key elements of the GRP to demonstrate and test the allies’ willingness and ability to implement them,⁷⁴ even if later stages of the exercises may still reflect more politically fictitious (and, hence, palatable) scenarios of actual conflict.

Conclusion

Despite the progress made since 2020, U.S.-Australia force posture cooperation remains limited by the lack of alliance institutionalization and political agreement, especially domestically in Australia, on its aims and objectives. This is not helped by the fact that the deployment to Australia of U.S. long-range naval and air strike forces tends to draw attention to thorny questions of vertical escalation as part of that cooperation. But at a more fundamental level, Australian willingness to participate in these activities is itself a form of deterrence by horizontal escalation, which is more politically palatable and relevant for Australia’s contribution to multilateral deterrence.

In the next phase of U.S.-Australia force posture cooperation, success should not just be measured by increased U.S. activity in Australia. Rather, it should be judged by whether it leads to greater complementarity between U.S. and Australian force postures and structures in general, and the extent to which it facilitates the contribution by third countries, especially in Europe, to multilateral deterrence. Although the 2023 DSR and 2024 NDS had little to say on the alliance’s implications for Australia’s national defense effort, the new direction they set for the ADF has widened the door for greater alignment between both allies’ defense preparations. The United States and Australia should grasp this opportunity for the next phase of their force posture cooperation.

This research was supported by the Australian Government through a grant by the Australian Department of Defence. The views expressed herein are those of the authors and are not necessarily those of the Australian Government or the Australian Department of Defence.

Notes