Summary: This article argues that Australia now has access to the same kind of autonomous, distributed littoral capability that has proven decisive in the Strait of Hormuz – and that it already exists domestically. Strategic advantage no longer comes from single platforms, but from integrated networks of autonomous subsurface, surface, aerial and data systems providing persistent maritime awareness. These capabilities are commercially mature, affordable, and align directly with Australian defence strategy. The key decision is whether Australia chooses to build and scale them sovereignly now, or delays and becomes dependent on foreign solutions.

A New Wave of Capability.

The capability that changes the equation already exists, is available in Australia, and ready to be deployed at scale. The only question is whether Australia chooses to build it.

Parts 1 and 2 of this series established the strategic argument. The Strait of Hormuz has demonstrated, with the sort of clarity that only war provides, that autonomous and robotic systems operating in the littoral can achieve strategic effects far beyond their direct cost. Iran's experience shows that a middle power facing a great power adversary can leverage geography, autonomy, and distributed capability to achieve strategic denial and impose costs in ways that out-manoeuvre conventional military logic. And Australia, a middle power with extraordinary maritime geography, an undersurveilled littoral region to our north, and an alliance relationship that has become strategically complex, has compelling and urgent reasons to apply these lessons.

The question that remains is: what does the capability actually look like, and who builds it?

An Integrated System, not a Platform

The most important insight from modern autonomous maritime operations – in the Hormuz, the Black Sea, the Red Sea – is that a decisive advantage doesn’t come from any single platform, once called a ‘capital ship’. The character of war has changed. Instead, advantage stems from the integration of smaller autonomous platforms. These work together to seamlessly combine undersea and surface sensing, aerial awareness, and data intelligence into a clear operational picture that provides a persistent, distributed, and cost-effective presence across a vast maritime area without needing a continuous manned commitment.

Consider what such an integrated system needs. First, it requires persistent subsurface awareness: the ability to track what occurs beneath the surface across large areas, continuously, without deploying costly crewed assets for each surveillance task. Second, it demands autonomous surface platforms: vessels capable of patrolling, monitoring, and responding in limited coastal and littoral zones, extending ranges beyond what crewed ships can sustain at similar costs. Third, ocean intelligence collected from autonomously deployed sensors forms the complete picture: merging raw data from acoustic, environmental, surface, and subsurface sensors into an operational view that commanders can act on in near-real time. Fourth, a shared operating framework for distributed decision-making and control: reliable, sovereign-controlled connectivity that links all components and stays under Australian control regardless of alliance changes.

This is not a theoretical capability. It all exists, it is commercially proven, and it is available in Australia right now.

Sub-Surface: The Eyes Beneath

The foundation of lasting littoral awareness is subsurface intelligence. Compact, modular autonomous underwater vehicles, operating in survey, monitoring, and acoustic sensing roles, can provide continuous coverage of approaches and chokepoints that would otherwise require dozens of manned vessels to replicate. This can be achieved at a fraction of the operational cost and with zero risk to crew. These systems can map bathymetry, monitor environmental conditions, conduct passive acoustic monitoring for submarine and surface activity, and perform visual inspections of underwater infrastructure – all autonomously, continuously, and without putting anyone in harm's way.

In a defence context, passive acoustic monitoring is especially important. A network of Autonomous Underwater Vehicles (AUVs) patrolling steadily along Australia's northern approaches would offer a significantly better level of subsurface situational awareness than what is currently accessible to the ADF. Acoustic signatures that would pass undetected beneath the threshold of conventional surveillance limits can become trackable, identifiable, and actionable. The kind of asymmetric advantage Iran has gained through its underwater autonomous systems – persistent presence, low signature, continuous intelligence – is now within Australia's reach using technology that is deployable today.

Surface and Air: Presence at Range

Persistent maritime domain awareness also requires ongoing surface presence, and ongoing surface presence depends on autonomous surface vessels capable of operating at extended ranges without continuous human oversight. Autonomous surface platforms in the littoral domain serve multiple roles simultaneously: maritime patrol, over-the-horizon communications relay, sensor hosting, and as launch and recovery platforms for subsurface vehicles that extend their effective operational range.

This last capability is transformative. An autonomous surface vessel operating 200 kilometres offshore can deploy and recover subsurface vehicles, extending the reach of the entire integrated system into waters that would otherwise require a crewed vessel to access. Aerial platforms operating from the same surface system extend surveillance reach even further, providing broad-area ISR that feeds into the common operational picture. The result is a system that covers vastly more ocean, continuously, than any crewed force of a similar cost could sustain.

Ocean Intelligence: Turning Data into Decisions

Raw sensor data alone does not constitute situational awareness. A network of autonomous systems produces large amounts of acoustic, environmental, and positional data that are operationally useless without the ability to fuse, analyse, and display it as an actionable picture. The intelligence layer – the data integration and presentation platform above the hardware – is where the true operational value of an integrated autonomous system is ultimately realised.

A purpose-built data intelligence platform that integrates feeds from subsurface, surface, and aerial autonomous systems, and presents them through a common operating picture that commanders can interrogate and act on, is the capability that transforms a collection of robotic platforms into a genuine maritime intelligence system. It is also the layer where sovereign protection matters most: the data flowing through this architecture concerns Australia's most sensitive maritime approaches, and it must remain under Australian control, protected by Australian-standard cybersecurity frameworks, on networks that are not dependent on foreign infrastructure.

The ADF already knows it needs this

The strategic argument presented here is not made in isolation. The Australian Government's 2024 National Defence Strategy and Integrated Investment Program allocated about AUD $1 billion to accelerate investment in robotic and autonomous systems, clearly recognising that autonomous systems provide ‘the opportunity to generate affordable mass, increase operational range, and improve force protection across all domains.’ The Australian Strategic Policy Institute has stated that the ADF urgently needs to expand its autonomous capabilities to develop a credible denial strategy, describing autonomous systems as offering ‘a different calculus’ to traditional specialised platforms.

The Army's Littoral Manoeuvre Group and its force development priorities, including integral hydrographic survey capability, logistics over the shore, and maritime domain force protection, exemplify the forward-thinking ADF formation that is already asking the right questions. The strategic logic, investment framework, and operational needs are all in place. What remains is the decision to genuinely partner with Australian sovereign companies capable of delivering.

The Industrial Argument: Why Sovereign Matters

There is an industrial argument here that is just as important as the strategic one. Australia's Defence Strategic Review emphasised genuine political will to expand the sovereign defence industrial base. The question is what that growth will be aimed at. Hopefully not large offshore primes operating nominally Australian subsidiaries. Investing in sovereign autonomous maritime capability yields compounding returns that exquisite foreign-supplied platform programmes cannot match.

Sovereign investment creates intellectual property that Australia owns and controls. It is not licensed from a US prime, is not subject to ITAR restrictions, and is not reliant on any foreign government's export policies. It helps develop an industrial workforce of engineers, operators, and maintainers with skills that can transfer across defence and commercial sectors. It produces capability that can be scaled at a fraction of the cost of traditional platforms, offering more sovereign capability per dollar of defence investment than any sophisticated programme can provide. Additionally, it offers export potential because the northern littoral challenge is not unique to Australia. Every Indo-Pacific nation with an island or archipelagic geography and an interest in maritime domain awareness faces a similar issue. Australian-developed, Australian-proven autonomous maritime capability is exportable in a way that makes it both commercially and strategically advantageous.

The Moment for Decision

The window for making a decision with genuine strategic impact is limited. The Hormuz conflict, like Ukraine before it, is accelerating the global development of autonomous maritime doctrine, capability, and industrial investment. Nations that act now will gain the operational experience, industrial capacity, and doctrinal frameworks that will shape littoral maritime power for the next generation. Those that delay will end up purchasing foreign-developed capability and accept the dependency that makes their security reliant on other governments' decisions.

Australia has an advantage Iran never had: the ability to build sovereign, autonomous maritime capabilities from a position of relative security and learn from recent events in Ukraine and the Persian Gulf. Iran developed its asymmetric capabilities under sanctions and threat, opposing a superpower. Ukraine developed theirs during a war of existential survival. If it chooses, Australia can develop this kind of capability carefully and in true partnership with allies, while maintaining control over the outcome.

The Strait of Hormuz has highlighted a vital strategic lesson written in oil on a canvas of sand and water. A middle power facing a great power in a confined maritime area is achieving strategic effects through autonomous, distributed, littoral-focused capability that no amount of traditional military investment could have provided at the same cost, depth, and resilience. Those working to fulfil Australia’s national strategy of strategic denial have the opportunity to write the same lesson. The question remains if Australia is the author or the subject.