Introduction

The release of the 2026 National Defence Strategy (NDS) marked a further evolution in Australia’s strategic thinking following the 2023 Defence Strategic Review (DSR) and the 2024 National Defence Strategy. While earlier strategic documents identified the rapid deterioration of Australia’s strategic environment, the 2026 NDS consolidates this shift into a more mature framework centred upon national defence, self-reliance, deterrence by denial, sovereign resilience, and integrated campaigning (Department of Defence 2026).

The 2026 NDS acknowledges that Australia faces the most challenging strategic circumstances since the Second World War. Intensifying strategic competition across the Indo-Pacific, accelerated military modernisation, coercive statecraft, cyber disruption, grey-zone activities, supply chain vulnerabilities, and the increasing risk of regional conflict collectively require a fundamental reassessment of how Australia conceives and employs military power (Department of Defence 2026).

Importantly, the 2026 NDS moves beyond viewing defence solely through the lens of platform acquisition or expeditionary capability. Instead, it advances a concept of national defence that integrates military power with national preparedness, sovereign industrial capability, civil resilience, and whole-of-government coordination. The strategy explicitly recognises that future conflict may involve prolonged disruption to logistics, infrastructure, communications, energy networks, and supply chains. Consequently, Defence must be capable not only of combat operations, but also of sustaining national resilience under conditions of strategic pressure.

Within this environment, the Australian Army faces a critical question regarding its enduring strategic purpose.

This is not merely a debate concerning force structure, equipment, or institutional reform. Rather, it concerns the Army’s theory of relevance within Australia’s evolving national defence framework.

Carl Builder argued that military institutions require coherent theories explaining who they are, why they exist, and how they contribute strategically to national objectives (Builder 1989). Without such a theory, military organisations risk fragmentation, pursuing technological modernisation or bureaucratic competition without a coherent understanding of purpose.

Historically, the Australian Army has demonstrated considerable adaptability. From continental defence during the Second World War, to counterinsurgency operations in Southeast Asia, expeditionary campaigns in the Middle East, stabilisation operations in the Pacific, and domestic support during natural disasters and pandemics – the Army has repeatedly evolved to meet government expectations.

However, the strategic environment described by the 2026 NDS requires more than institutional adaptation alone. It requires conceptual clarity regarding the Army’s role within a strategy of national defence.

The Army Plan and the broader integrated force construct already imply elements of such a theory through their emphasis on readiness, littoral manoeuvre, resilience, long-range land-based effects, and sustained campaigning (Australian Army 2023). Yet these concepts require articulation within a coherent framework capable of explaining the Army’s enduring relevance.

A theory of the Australian Army in the 2026 NDS era might therefore be expressed as follows:

The Australian Army is Australia’s persistent littoral land force: it generates credible land power to deny adversary coercion, secure Australia’s northern approaches, project influence with regional partners, protect critical infrastructure and populations, and enable the integrated force to deter, fight, and win in defence of Australia and its interests.

This theory reflects the central themes of the 2026 NDS. It situates the Army within a broader strategy of denial, integrated force design, national resilience, and sustained regional competition. Most importantly, it explains that the Army’s purpose extends beyond battlefield victory alone. Army contributes directly to making Australia harder to coerce, harder to isolate, harder to disrupt, and harder to defeat.

National Defence and Self-Reliance

The defining strategic concept of the 2026 NDS is the transition toward a genuine model of national defence grounded in increased Australian self-reliance. While Australia continues to rely upon alliances and regional partnerships, the strategy recognises that Australia must possess greater sovereign capacity to defend its territory, infrastructure, population, and approaches independently if necessary (Department of Defence 2026).

This represents a significant evolution in Australian defence policy. Previous defence strategies often assumed that Australia would possess lengthy warning times and enjoy secure access to global supply chains and allied sustainment. The 2026 NDS rejects these assumptions. It explicitly acknowledges that Australia may face strategic disruption with reduced warning, contested logistics, cyber attacks, infrastructure degradation, and pressure upon critical national systems.

Within this framework, land power becomes increasingly important.

Air and maritime power provide Australia with the capacity to project force, conduct long-range strike, shape regional deterrence, and deny adversary manoeuvre. However, only land forces can establish enduring physical control over infrastructure, populations, logistics hubs, transport corridors, ports, airfields, fuel facilities, and communication networks.

Colin Gray argues that the political purpose of war ultimately requires the capacity to control people, territory, and the physical infrastructure upon which societies depend – a requirement that precision strike and autonomous systems can shape but not substitute for (Gray 2016). This insight does not reduce all modern conflict to attrition, but it does explain why land power retains enduring relevance: only physical presence can translate military effect into lasting political outcome.

For Australia, the implications are profound. Northern Australia contains critical infrastructure essential to joint force operations, including ports, airbases, fuel systems, logistics nodes, communications infrastructure, and transport corridors. The security of these systems underpins the broader integrated force.

Consequently, the Army’s role within national defence is not limited to expeditionary operations abroad. Rather, Army provides government with the means to secure critical terrain, sustain sovereign resilience, protect populations, and maintain operational continuity during crisis or conflict.

The 2026 NDS therefore reinforces the enduring relevance of land power by recognising that national defence ultimately rests upon the ability to preserve the physical and societal foundations upon which military operations depend.

Strategy of Denial and the Army’s Role

Deterrence by denial remains central to Australian defence strategy in the 2026 NDS. However, the concept of denial has evolved beyond traditional understandings focused solely upon maritime and air strike capabilities.

The strategy recognises that denial requires an integrated force capable of preventing adversaries from achieving political and military objectives across multiple domains simultaneously (Department of Defence 2026). Denial therefore involves not only the destruction of enemy forces, but also the protection of national resilience, sustainment systems, infrastructure, decision-making capacity, and regional access.

Within this framework, the Army contributes to denial through several distinct functions.

First, Army provides persistent land presence across northern Australia and the littoral environment. Unlike ships or aircraft, land forces can sustain enduring physical presence among populations and infrastructure over extended periods.

Second, Army contributes to denial through littoral manoeuvre and long-range land-based effects capable of supporting maritime denial operations. The Army’s littoral evolution enables it to contribute directly to joint force operations across archipelagic and coastal terrain.

Third, Army strengthens denial through protected logistics, sustainment, engineering, health support, mobility, and force protection. The war in Ukraine has demonstrated that sustainment and logistics are not peripheral to modern warfare but central determinants of strategic endurance (Freedman 2023).

Finally, Army contributes to denial by increasing the difficulty and cost of coercion against Australia and its regional partners. Persistent land presence, integrated joint operations, and regional engagement collectively complicate adversary planning and strengthen deterrence credibility.

The Army’s contribution to denial is therefore not confined to large-scale close combat operations alone. Rather, it involves generating strategic friction, resilience, persistence, and operational depth across the broader national defence enterprise.

Northern Australia and the Littoral Environment

The 2026 NDS reinforces the strategic significance of northern Australia and the broader Indo-Pacific littoral environment. Australia’s geography is inherently maritime and archipelagic. Critical trade routes, military infrastructure, regional partnerships, and operational approaches are concentrated within complex coastal and littoral terrain.

As a result, the Army’s evolving littoral focus represents not a departure from land warfare, but its modernisation within Australia’s strategic context.

Chief of Army Lieutenant General Simon Stuart described this shift as the Army’s “littoral pivot,” emphasising the Army’s role within maritime strategy through land control, sustainment, sensing, protection, and distributed joint effects (Stuart 2025).

The 2026 NDS further develops this concept by emphasising distributed operations, northern infrastructure resilience, and integrated campaigning across the Indo-Pacific (Department of Defence 2026).

Importantly, littoral operations do not reduce the importance of land power. Rather, they reinforce it.

Future conflict within the Indo-Pacific is likely to occur across densely populated coastal regions, ports, islands, archipelagos, urban corridors, and contested infrastructure networks. These environments require forces capable of operating persistently among populations while integrating maritime, air, cyber, space, and land effects.

Only land forces can consistently secure terrain, protect infrastructure, sustain distributed operations, and maintain enduring presence within these environments.

The Army’s littoral role therefore reflects several strategic realities:

• Australia’s security is inseparable from its northern approaches and maritime environment.
• Future campaigning will involve dispersed and contested archipelagic terrain.
• Joint force sustainment depends upon secure land infrastructure.
• Strategic competition increasingly occurs among populations and regional communities.
• Resilience and persistence are essential to deterrence.

The Army’s theory of land power must therefore place littoral operations at the centre of its strategic identity.

Lessons from Ukraine and the Middle East

The 2026 NDS places increased emphasis upon lessons emerging from contemporary conflicts, particularly the wars in Ukraine and the Middle East. These conflicts have reinforced several enduring truths regarding warfare that are directly relevant to the Australian Army.

The war in Ukraine has demonstrated that mass, industrial capacity, logistics, resilience, and sustained mobilisation remain decisive factors in prolonged conflict (Freedman 2023).

Second, the conflicts have highlighted the vulnerability of logistics networks, infrastructure, communications systems, fuel supply, and industrial production. Strategic endurance depends not only upon frontline combat capability, but also upon the capacity to sustain operations over time.

Third, the conflicts have reinforced the continuing importance of land forces. Despite the widespread use of drones, cyber operations, missiles, and long-range fires, control of territory and populations continues to depend upon physical land presence.

Finally, these conflicts have demonstrated the strategic significance of societal resilience. Civil preparedness, industrial mobilisation, reserve forces, national morale, and infrastructure protection all contribute directly to military effectiveness.

The 2026 NDS incorporates these lessons by emphasising sovereign industrial capability, supply chain resilience, preparedness, and integrated national defence.

For the Army, these lessons reinforce the importance of:

• readiness and force-in-being capability
• protected sustainment and logistics
• dispersed and survivable operations
• engineering and infrastructure protection
• reserve integration and mobilisation
• resilience across contested environments
• long-duration campaigning
• warfighting credibility

These lessons challenge assumptions that future conflict will necessarily be short, technologically decisive, or conducted at distance from the Australian mainland.

Instead, they reinforce the requirement for a resilient Army capable of enduring sustained strategic competition and conflict.

Integrated and Focused Force Design

The 2026 NDS further advances the concept of an integrated and focused force capable of generating coordinated effects across domains. Integration, however, should not be confused with interchangeability.

Each service contributes unique strategic functions. The Army’s value lies not in replicating maritime or air power, but in enabling and sustaining joint operations through land control, protection, logistics, engineering, command systems, and persistence.

Land forces secure ports and airfields required for joint access. They establish sustainment hubs and logistics corridors. They protect critical infrastructure and communications systems. They provide mobility, health support, engineering, and force protection essential to sustained operations.

Without secure land infrastructure and sustainment networks, maritime and air operations become increasingly fragile over time. This is particularly relevant within Australia’s operating environment, where vast distances and limited infrastructure create profound sustainment challenges. The Army’s role within the integrated force is therefore foundational rather than supplementary.

The 2026 NDS also emphasises focused force design. Defence cannot prepare equally for every contingency. Consequently, capability development must align with Australia’s most likely strategic requirements.

For the Army, this means prioritising:

• littoral manoeuvre
• northern Australia operations
• long-range land-based effects
• protected logistics and sustainment
• resilient command and communications
• infrastructure protection
• integrated air and missile defence
• regional engagement and access
• mobilisation and reserve integration

These priorities align directly with the strategic realities identified in the 2026 NDS.

Resilience, Preparedness, and Sovereign Capability

One of the most important developments within the 2026 NDS is the elevation of resilience and preparedness as central defence priorities.

The strategy explicitly recognises that future conflict may involve disruption to infrastructure, cyber networks, fuel supplies, communications, transportation systems, and industrial production. Consequently, national defence requires a broader conception of security extending beyond traditional military operations. The Army occupies a unique position within this framework.

Because of its organisational structure, geographic dispersion, logistics capability, engineering capacity, and ability to operate persistently within domestic environments, Army contributes directly to national preparedness and resilience.

Recent bushfires, floods, pandemics, and infrastructure disruptions demonstrated both public expectations and practical requirements for Army support during national crises. However, these domestic tasks should not be viewed as separate from warfighting. Rather, domestic operations reinforce many of the same competencies required during conflict, including:

• logistics and sustainment
• command and control
• mobility and engineering
• communications
• interagency coordination
• distributed operations
• leadership under pressure
• infrastructure protection

The risk is not that Army conducts domestic operations. The risk is allowing these operations to redefine Army’s identity away from warfighting. The Army’s domestic utility derives precisely from its warfighting foundations.

The 2026 NDS therefore strengthens the Army’s strategic relevance by recognising that military power and national resilience are increasingly interconnected.

Regional Partnerships and Strategic Competition

The 2026 NDS places significant emphasis upon regional partnerships, collective deterrence, and persistent engagement across the Indo-Pacific.

Strategic competition increasingly occurs below the threshold of declared conflict. Influence, legitimacy, access, partnerships, and persistence often shape strategic outcomes as much as conventional military power.

David Kilcullen argues that contemporary competition increasingly revolves around the human domain, where relationships, legitimacy, and societal influence become central to strategic success (Kilcullen 2020). This is particularly relevant within the Indo-Pacific, where strategic influence is often built through sustained presence, military cooperation, training partnerships, humanitarian assistance, and institutional relationships.

The Australian Army contributes directly to this environment because armies operate among populations and partner forces. Army engagement activities across Southeast Asia and the Pacific strengthen interoperability, access, trust, and regional resilience. These activities contribute directly to deterrence by demonstrating Australia’s enduring commitment to regional stability.

Importantly, regional engagement should not be viewed as a peacetime distraction from warfighting. Rather, it forms part of integrated deterrence. Persistent regional partnerships:

• strengthen access and basing arrangements
• improve interoperability
• complicate adversary coercion
• reinforce collective resilience
• support intelligence and situational awareness
• strengthen regional legitimacy
• enhance strategic influence

The Army’s contribution to regional competition therefore extends beyond combat capability alone. It involves the sustained generation of strategic relationships that strengthen Australia’s security environment over time.

Industrial Mobilisation and Sustained Campaigning

A further defining feature of the 2026 NDS is its recognition that future conflict may require sustained mobilisation over extended periods.

The strategy therefore places increased emphasis upon sovereign industrial capability, domestic manufacturing, supply chain resilience, and national preparedness. This reflects lessons from Ukraine, where industrial production, ammunition stockpiles, repair systems, logistics, and mobilisation capacity proved critical to sustained resistance.

For Australia, sustained campaigning presents unique challenges due to geography, distance, and limited industrial depth. The Army plays an essential role within this framework because prolonged land operations require resilient sustainment systems, engineering support, protected logistics, and infrastructure security.

The Army also provides critical links between Defence, industry, regional communities, and civil authorities. Reserve forces become particularly important within this context. The 2026 NDS increasingly recognises the importance of mobilisation frameworks capable of expanding national capacity during crisis.

Consequently, the Army’s theory must incorporate not only combat operations, but also its role within broader national mobilisation and strategic endurance. A force designed solely for short-duration expeditionary operations would be poorly aligned to the realities described within the 2026 NDS. Instead, the Army must be capable of contributing to sustained campaigning within contested and degraded environments over extended periods.

The Risk of Strategic Drift

Without a coherent theory, the Australian Army risks strategic drift.

This may manifest through excessive emphasis upon domestic support at the expense of warfighting readiness, technological modernisation disconnected from strategic purpose, or fragmentation across competing priorities.

A coherent theory provides institutional focus.

It explains:

• why the Army exists
• what strategic effects it provides
• how it contributes to national defence
• what competencies it must prioritise
• how it supports deterrence and resilience

Most importantly, it protects institutional identity.

The Army cannot become merely a general-purpose government workforce in uniform. Its legitimacy derives from its capacity to apply disciplined violence on behalf of the state when required. Every other contribution flows from that core responsibility.

Conclusion

The 2026 National Defence Strategy consolidates Australia’s transition toward a model of national defence centred upon self-reliance, integrated deterrence, sovereign resilience, and sustained campaigning. Within this strategic environment, the Australian Army’s enduring relevance becomes increasingly clear.

The Army exists not simply to fight wars abroad, nor solely to assist during domestic crises. Rather, it provides government with persistent land power capable of securing terrain, protecting infrastructure and populations, enabling joint operations, sustaining resilience, supporting regional partnerships, and contributing directly to deterrence by denial.

The Army’s littoral evolution does not diminish the importance of land power. Instead, it modernises its application within Australia’s strategic geography.

Future conflict within the Indo-Pacific is likely to involve contested littoral terrain, disrupted logistics, prolonged strategic competition, and pressure upon national resilience. In such an environment, Australia requires a land force capable of operating persistently across northern Australia and the region while enabling the integrated force to deter, fight, and endure.

The Australian Army is therefore not peripheral to national defence, it is fundamental to it.