The Australian Army’s Evolving Role in Deterrence Strategy: Rethinking Land Power in the Indo-Pacific

The Australian Defence Force is undergoing a fundamental strategic transformation.

After decades focused on expeditionary operations in the Middle East, Australia’s military is pivoting to address the challenge of great power competition in the Indo-Pacific.

At the center of this shift lies a critical question: what role should the Australian Army play in deterring potential adversaries in a region dominated by maritime geography?

A research paper from the Australian Army Research Centre challenges conventional wisdom about deterrence strategy and argues that the Army’s traditional mission of taking and holding territory remains more relevant than ever, even in an era increasingly defined by long-range strike capabilities and advanced technology.

The Deterrence Revolution in Australian Strategy

Australian defence policy has historically relied on alliance relationships and expeditionary capabilities rather than deterrence. The Army’s role was largely confined to supporting coalition operations overseas, with deterrence left to nuclear-armed allies or Australia’s submarine and air force capabilities. This began changing with the 2020 Defence Strategic Update, which formally embraced deterrence as a core mission, followed by the 2023 Defence Strategic Review’s emphasis on “deterrence by denial” across Australia’s northern approaches.

This shift represents more than just strategic reorientation. It fundamentally challenges how the Australian Army must think about its role, structure, and deployment. Unlike air and naval forces that can project power from afar, land forces are inherently “politically entangling,” as strategist Colin Gray noted. When soldiers are deployed forward, they signal commitment in ways that ships and aircraft cannot match.

Yet this political advantage comes with operational complications. Modern warfare increasingly favors mobility, dispersion, and survivability which are qualities that can conflict directly with deterrence requirements for visible, persistent presence that adversaries cannot easily dismiss or circumvent.

Three Models of Military Deterrence

To understand how the Army might contribute to deterrence, researchers Dr. Andrew Carr and Professor Stephan Frühling from the Australian National University developed a framework identifying three distinct models of forward military presence:

• Thin Tripwires represent small forces designed primarily to be sacrificed in order to trigger larger retaliation. These forces have limited operational capability but serve as political “hostages” that guarantee escalation if attacked. The British Army’s reserve presence in the Falkland Islands before 1982 exemplified this approach and its ultimate failure when Argentina invaded despite the presence of Royal Marines.
• Thick Tripwires are more substantial forces capable of forcing adversaries to commit significant resources and cross clear thresholds from “grey zone” activities to open military conflict. The Allied garrison in West Berlin during the Cold War represented this model which was large enough to resist covert takeover attempts but never expected to stop a determined Soviet assault. Instead, it ensured any Eastern Bloc move against the city would constitute unambiguous aggression requiring massive military commitment.
• Forward Defence involves deploying forces actually capable of denying adversaries their objectives, albeit within broader strategies for reinforcement and escalation. The UK’s current Falklands garrison exemplifies this approach, with substantial air defense capabilities, fighter aircraft, and rapid reinforcement capacity designed to prevent successful invasion rather than merely trigger retaliation.

Each model reflects different balances between political signaling and operational effectiveness, with profound implications for force structure, training, and deployment patterns.

The Credibility Challenge

The research reveals a fundamental tension at the heart of contemporary Australian strategic thinking. Current defense planning increasingly emphasizes long-range strike capabilities as the primary deterrent against potential adversaries. This approach assumes that the ability to impose costs through missile attacks on high-value targets will discourage aggression.

However, the historical record for deterrence based primarily on punishment rather than denial is mixed at best. Threats to retaliate only remain credible if decision-makers believe they can achieve meaningful strategic effects through such retaliation. A “tripwire” posture that relies solely on long-range strikes faces the same credibility problems as any punishment-based threat: executing it after deterrence fails risks further escalation with no prospect of changing the conflict’s outcome.

This credibility gap becomes particularly acute for smaller powers like Australia. An adversary might calculate that Australia would be unwilling to escalate further after suffering initial losses, especially if long-range retaliation fails to restore the status quo. The side with the least ability to replenish forces faces the greatest risk in throwing additional resources into what might already be a lost cause.

The Maritime Geography Paradox

Critics might argue that emphasizing land forces for Indo-Pacific deterrence misunderstands the region’s fundamentally maritime character. If conflict occurs primarily at sea or through air power, land-based tripwires might never be triggered, making Army contributions irrelevant.

This objection misses the crucial point that territorial control ultimately determines conflict outcomes, even in maritime regions. Islands, ports, and coastal positions provide the bases from which sea and air power operate. More fundamentally, territorial integrity represents the stakes for which most conflicts are fought. An adversary’s ability to seize and hold territory whether Australian islands or partner nation facilities transforms the strategic situation in ways that purely maritime or aerial actions cannot.

The challenge for Australia lies in deploying land forces that can credibly defend such territory rather than merely serving as symbolic hostages. This requires capabilities for actual area denial rather than just political signaling.

Force Structure Implications

Shifting the Army toward forward defense creates significant force structure challenges. Traditional military units organized for joint warfighting may not suit the specific political and operational requirements of forward presence missions.

Several factors complicate this transition:

• Rotational versus Permanent Deployment: Maintaining forward presence through regular unit rotations requires roughly three times the forces actually deployed at any given time, accounting for preparation, deployment, and reset phases. This approach offers strategic mobility advantages and provides broader force experience, but demands substantial resources. Alternatively, establishing permanent specialized units creates forces that cannot easily be replaced or redeployed for other missions.
• Political versus Operational Optimization: Forces structured for maximum deterrent effect may not be optimally configured for combat effectiveness. During the Cold War, NATO’s Central Front deployment reflected political requirements for burden-sharing and German reassurance rather than operational logic. All major allies maintained separate sectors along the inner German border rather than concentrating forces for maximum defensive effectiveness.
• Technology Integration Challenges: The Army’s emerging long-range strike capabilities require integration with joint targeting networks and external intelligence systems. However, the political effectiveness of forward presence may depend on forces being visibly present and difficult to withdraw—qualities that can conflict with the mobility and concealment required for survivability against precision weapons.

Two Strategic Scenarios

The research examines how these considerations might apply to two potential scenarios for Australian Army forward presence:

Defending the Cocos and Christmas Islands represents the challenge of protecting remote Australian territory. These islands, located much closer to Southeast Asia than to mainland Australia, offer strategic value for controlling maritime approaches and submarine transit routes. However, their isolation and limited infrastructure create severe challenges for sustainable defense.

A thin tripwire approach might involve small surveillance units that could be quickly overwhelmed but would guarantee political escalation if attacked. A thick tripwire would require substantial defensive capabilities, armor, air defense, and engineering works, sufficient to force adversaries into unambiguous military action. Forward defense would demand organic capabilities to defeat landing forces and counter air attack, likely requiring significant permanent infrastructure and rapid reinforcement capacity.

Each approach involves different resource commitments and political risks. More importantly, each sends different signals about Australia’s determination and capabilities to regional audiences, including potential adversaries, allies, and the domestic population.

Supporting the Philippines on Palawan illustrates the complexities of forward presence in partnership contexts. Such deployment would need to balance deterring China while reassuring the Philippines, managing U.S. alliance dynamics, and addressing concerns from other regional partners about escalation risks.

The host nation becomes as much an audience as the potential adversary, creating additional signaling challenges. What reassures the Philippines about Australian commitment might differ significantly from what deters Chinese action. Australian forces would need capabilities aligned not just with military effectiveness but with Philippine expectations about the nature and extent of support they could expect.

The Coalition Reality

Perhaps the most significant finding concerns the limitations of “self-reliant” deterrence. The research suggests that Australia lacks the scale and strategic depth to achieve credible deterrence independently against major power threats. This does not diminish the Army’s potential contributions but rather clarifies how they should be understood.

Effective Australian deterrence likely requires U.S. alliance support, with Australian forces serving to ensure direct involvement in any conflict rather than providing independent deterrent effects. This “coalition tripwire” model differs fundamentally from self-reliant approaches but may offer more realistic prospects for success.

Such an approach would focus Australian Army capabilities on ensuring that conflicts cannot be resolved without triggering broader alliance responses. Rather than independently deterring major powers, Australian forces would guarantee that aggressive actions face coalition resistance from the outset.

Regional Diplomatic Considerations

Forward deployment of Australian forces, particularly those with long-range strike capabilities, raises complex diplomatic challenges. Land-based missiles positioned on Christmas Island or in partner nations would likely cover portions of other countries’ territory or maritime claims, potentially complicating relationships with Indonesia, Malaysia, and India.

These concerns extend beyond mere geographic coverage to questions about escalation dynamics and regional stability. Partners may value Australian security contributions while worrying about becoming targets in conflicts not directly related to their core interests.

Success requires extensive consultation and coordination with regional partners, potentially limiting deployment flexibility but ensuring broader strategic coherence. The political logic of forward presence demands that such deployments enhance rather than undermine regional relationships.

Modernization Priorities

The analysis suggests several priorities for Army modernization beyond simple procurement of long-range weapons:

• Defensive Integration: Land forces need capabilities that complement rather than duplicate air and naval systems. This might emphasize short-range air defense, anti-armor systems, and engineering capabilities that can deny adversary use of captured facilities.
• Rapid Reinforcement: Given the costs of large permanent garrisons, the ability to quickly reinforce small forward elements becomes crucial. This requires strategic mobility capabilities, pre-positioned equipment, and infrastructure that can rapidly expand force levels during crises.
• Joint Interoperability: Effective deterrence increasingly depends on joint targeting networks and integrated intelligence systems. Army units need capabilities to contribute to and benefit from joint operations rather than operating independently.
• Infrastructure Protection: Forward presence forces often must defend the very facilities, ports, airfields, communications sites, that enable their own sustainment and reinforcement. This creates requirements for specialized engineering and security capabilities.

The Enduring Relevance of Territory

The research concludes that the Army’s traditional mission of taking and holding territory remains crucial despite the Indo-Pacific’s maritime character. Territorial control provides the foundation for sustained military operations and represents the ultimate stakes in most conflicts.

This insight challenges recent emphasis on long-range strike as the primary deterrent capability. While such systems certainly contribute to deterrent effects, they cannot substitute for the ability to actually defend key terrain and infrastructure.

Moreover, the political effectiveness of deterrence depends significantly on adversary perceptions of defender resolve and capability. Forces that can demonstrate actual defensive success provide more credible deterrent signals than those that can only threaten retaliation.

Strategic Implications

The transformation of Australian Army roles in deterrence strategy reflects broader changes in the strategic environment. Traditional approaches that separated peacetime engagement from wartime response no longer adequately address contemporary challenges characterized by persistent competition below the threshold of open conflict.

This environment demands forces capable of contributing across the spectrum from competition through crisis to conflict. Such contributions require different capabilities and organizational approaches than traditional warfighting or peacekeeping missions.

The challenge for Australian defense planning lies in developing Army capabilities that can credibly contribute to deterrence while maintaining effectiveness for other missions. This may require accepting some operational compromises in favor of political effectiveness, or developing specialized units optimized for forward presence missions.

Looking Forward

The evolution of Australian Army roles in deterrence strategy remains in early stages. Current force structure decisions will shape capabilities and options for decades to come. The research suggests that these decisions should prioritize forward defense capabilities over purely punitive approaches, while recognizing the coalition context within which Australian deterrence must operate.

Success will require careful integration of political and operational considerations, extensive regional consultation, and realistic assessment of Australian capabilities and limitations. Most importantly, it demands recognition that effective deterrence ultimately depends on the ability to defend successfully rather than merely threaten retaliation.

The Australian Army’s contribution to deterrence may look quite different from traditional concepts of land warfare, but its fundamental mission—controlling territory and demonstrating national resolve—remains as relevant as ever. The challenge lies in adapting these enduring requirements to contemporary strategic conditions while building the capabilities needed for success in an uncertain future.

The report entitled Forward Presence for Deterrence: Implications for the Australian Army was published in August 2023.

And can be found here:

https://researchcentre.army.gov.au/library/occasional-papers/15