Australia’s 2023 Defence Strategic Review ^[1] (DSR) prescribed the ADF a ‘strategy of denial’ using an Anti-Access/Area-Denial (A2/AD) force structure to deny adversaries the ‘freedom of action to militarily coerce Australia and to operate against Australia without being held at risk’. The ADF’s primary area of interest spans from the north-eastern Indian Ocean to Australia’s northern approaches in Southeast Asia to the Pacific.

It identified capabilities ^[1] for denying enemy forces from approaching Australia that include undersea warfare assets, multi-domain long-range strike capacity, multi-domain capabilities for sea denial and localised sea control, as well as air and missile defence (AMD) systems. As Australia’s northern approaches through Southeast Asia and the South Pacific are archipelagic ^[2], they are covered with islands, rivers and ocean.

Specifically, the DSR gave the Australian Army several force structure priorities, including ‘littoral manoeuvre capability by sea, land and air’, long-range land and maritime strike capabilities and AMD capabilities. Littoral manoeuvre occurs close to shore, with Army intending ‘to achieve control of the maritime domain from the land, as well as projecting and sustaining force ashore’ ^[3]. The DSR also stipulated that the acquisition of medium-range ^[1] AMD systems ‘should be accelerated’ ^[1] because these capabilities are needed ‘urgently’ ^[1], noting that ‘off-the-shelf options must be explored’ ^[1]. The DSR concluded that ‘only by concurrently delivering these capabilities—littoral manoeuvre vessels, land-based maritime strike capabilities and infantry fighting vehicles—will Army be able to achieve the strategic and operational effect required of the ADF for National Defence and a strategy of denial’.

From this, it’s reasonable to draw the following conclusions:

1. The ADF must assert localised control across multiple warfare domains to deny Australia’s archipelagic northern approaches and the South Pacific to potential adversaries. Multi-domain control demands competence in undersea, anti-surface, and anti-air warfare. It also requires the use of AMD and long-range strike capabilities.

2. Defence is actively shifting Army’s identity towards multi-domain combat units, aimed at defensively denying ^[4] key archipelagic geography (like maritime choke points ^[5]) to adversaries through sea and air control ^[5]. The DSR’s force structure priorities for Army, such as littoral manoeuvre, long-range strike and AMD, suggest this. The idea of land-based multi-domain combat units isn’t new—it was floated in a 2018 US Army multi-domain operations ^[6] concept, a 2019 CSBA study ^[7] and a 2021 US Marine Corps stand-in forces ^[8] concept.

3. Army combat units will need to be road-mobile, deployable by Air Force airlifters, and deployable with Navy vessels, and Army’s future littoral manoeuvre vessels (LMVs).

4. Army wants to be capable of projecting force independently ^[9] into Australia’s archipelagic northern approaches and the South Pacific. The scale of the LMVs being procured indicates this—a medium sized LMV is planned to be capable of carrying a 70 tonne payload at a range of around 2,000 kilometres ^[9].

5. The urgency of delivering these capabilities will require the extensive use of off-the-shelf military procurement.

With the DSR’s strategic intent and capability priorities unpacked, particularly for Army, let’s consider what Army could acquire for its multi-domain combat units to contribute to the ADF’s strategy of denial.

Future Australian Army multi-domain combat units could include the following four groups: a Command Control Communications Headquarters (hereafter ‘C3HQ’) group, an AMD group, a strike group and a force protection group.

The C3HQ group would focus on integrating communications and sensors to help unit commanders find, track, target and engage enemy forces. Off-the-shelf solutions—like ‘Virtualised Aegis’ ^[10]—boast proven interoperability with existing communication systems, sensors and weapons for undersea warfare, anti-surface, strike and AMD missions. Army C3HQs could mirror the Combat Information Centre of Navy Hobart Class destroyers—harnessing existing Navy training structures and minimising duplication across the joint force while enhancing Army/Navy interoperability.

For communications, C3HQs would need datalinks, encrypted radios and satellite connectivity. For sensors, C3HQs could leverage ground-based radars that the ADF are already acquiring under the LAND 19 ^[11] and AIR 6500 ^[12] programs, and could also be supplemented with the new US Army LTAMDS ^[13] radar—offering 360 degree detection and tracking of ‘advanced and next-generation threats, including hypersonic weapons’ ^[13]. The LTAMDS radar is compatible with PAC-3 MSE ^[14] missile capabilities—a variant of the LTAMDS radar ^[15] is also compatible with the ADF’s new NASAMS ^[11] batteries for AMD missions. Additionally, the range of ground-based radars could be extended by fitting high-altitude balloons and uncrewed aerial vehicles (UAVs) with appropriate sensors ^[16]. And in littoral environments, C3HQs could deploy unmanned surface vehicles fitted with towed arrays—like the Australian ‘Bluebottle’ ^[17]—to detect enemy submarines.

The AMD group could then use C3HQ data to engage hostile aircraft, cruise missiles, ballistic missiles and boost-glide missiles. Terminal High Altitude Area Defense (THAAD ^[18]) batteries could defend against short, medium and intermediate ^[18] range ballistic threats both inside and outside the atmosphere at ranges of 150 to 200 kilometres ^[19].

Although a bespoke hypersonics defence system doesn’t exist, it might be possible to improve the intercept probability of existing PAC-3 MSE ^[20] interceptors using sensor data from the LTAMDS radar ^[13]. Japan is reportedly considering ^[21] this pathway to improve its defences against hypersonic threats.

In Australia, Army is acquiring new NASAMS ^[22] missile batteries to defend against aircraft, UAVs and cruise missiles. Each battery supports up to 72 AMD interceptors across 12 launchers ^[23] and is compatible with Navy’s RIM-162 ESSM interceptor ^[24]. This is important ^[16] because the ESSM has a speed of Mach 4+ and a range exceeding 50 kilometres, and can be upgraded to defeat low-signature targets and some ballistic missiles. In the future, NASAMS could potentially support other longer-ranged interceptors like the Skyceptor ^[25], with a range of around 200 kilometres ^[25].

In turn, the strike group could use C3HQ data and Army’s existing HIMARS ^[1] rocket launchers for land and maritime strike missions. In the short-term, HIMARS could be modified to support to support surface-launched LRASM ^[26] anti-ship cruise missiles with a range around 900 kilometres ^[27]. HIMARS can also support future PrSM ballistic missiles that have a planned range around 1,600 kilometres ^[27] for land and anti-ship strikes ^[28]. To deny enemy undersea forces, the strike group could use rotary-wing UAVs armed with very lightweight torpedoes weighing around 100 kilograms ^[29]. Alternatively, Air Force’s existing P-8As ^[30] or loitering Ghost Bat ^[31] UAVs could provide on-demand anti-submarine strikes with air-launched torpedoes.

Finally, the force protection group would focus on limiting the effectiveness of enemy attacks. Advanced camouflage and concealment methods—like multi-spectral camouflage ^[32]—could render Army units less detectable to enemy sensors. A counter-drone capability would be needed to prevent the enemy using low-cost swarms of drones for saturation attacks—the 40mm D40 ^[33] loitering drone has a range of 20+ kilometres ^[34] and is a prime example of this technology.

Army could also consider pairing innovative high-powered microwave counter-drone technology ^[35], for defeating drone swarms, with a counter rocket artillery mortar system—like Israel’s ‘Iron Dome’ ^[36]—in order to defend high-value assets within multi-domain combat units. Army might also consider adding cyber warfare capabilities and electronic protection vehicles fitted with countermeasures and decoys to this mix.

The DSR pivots Army’s identity away from Middle East land operations towards multi-domain combat units that focus on littoral manoeuvre and archipelagic denial capabilities. To do this, Army should consider fielding multi-domain combat units capable of handling high-intensity warfighting conditions and of serving as the nucleus of Army deployments. This approach would make Army’s force structure strong but flexible—multi-domain combat units could be tailored to specific mission requirements by reinforcing specific groups, reducing or omitting specific groups, or by adding detachments from other Army corps (such as combat engineers or mobile field hospitals).

The best news is that the technology to achieve Army’s goals already exist. For an idea of what is possible, the US Army took a clean-sheet mid-range capability battery design in July 2020 ^[37] all the way through to prototype by late 2022 ^[37]. Only with the right funding and high-level authority to remove all obstructions can the Australian Army prepare for a strategy of denial with the haste demanded by the DSR.