Summary: This article argues that the Strait of Hormuz has become a live demonstration of how modern maritime power is shifting from blue‑water dominance to contested littoral control. Iran has used low‑cost autonomous drones, mines, and sensor networks to deny a superior navy freedom of movement in shallow, complex waters. The lesson is that distributed, autonomous systems overturn traditional naval cost and power advantages. The warning for Australia and other middle powers is clear: chokepoint security now depends on mastering littoral autonomy, not just building big ships.

The Littoral is the Battlefield.

What the Strait of Hormuz is teaching the world about modern maritime power – and whether Australia is paying attention.

Over the last month, in the Strait of Hormuz, the most important military experiment of the 21st century has played out live. A war is being waged where strategic air power and intercontinental missile exchanges are not proving to be decisive. As the military saying goes, and to the US’s frustration, the enemy has a vote. They are fighting the war, and by any reasonable account, winning it, in the unglamorous shallows, with autonomous drone boats, undersea robotic vehicles, distributed sensor networks, and swarming craft operating in and above water that is too confined, too shallow, and too complex for conventional naval doctrine to fully master. The lessons being learned are not highly classified military secrets. They are visible to anyone willing to look.

Iran has effectively taken control of one of the world's most vital maritime chokepoints using systems that cost a fraction of what the US Navy can deploy in the same waters. Through explosive-laden autonomous surface vessels, stealthy underwater vehicles, passive acoustic monitoring networks, and mine barrages, Iran – with a fraction of the conventional naval power of its adversary – has effectively denied passage through a 33-kilometre stretch of water. This is a significant strategic achievement that has been achieved at a remarkably low cost.

Why the Littoral Changes Everything

The littoral zone – the coastal waters, straits, archipelagos, estuaries, and the contested in-shore and near-shore environment – has always been the strategically vital but operationally difficult space between the land and open ocean. Blue-water navies are designed for deep water; capital ships optimised for deep water are bulky and vulnerable when operating in littoral environments where shallow water impairs sonar performance, sea room to manoeuvre is limited, and the presence of civilian activity creates ambiguity that conventional rules of engagement often find difficult to resolve.

Iran recognised this long before the current conflict. For decades, the Islamic Revolutionary Guard Corps Navy crafted a doctrine specifically aimed at exploiting littoral complexity against a traditionally superior enemy. Their dispersed 'mosaic' approach spreads command authority so widely that even if key command nodes are lost, remaining forces can still act independently. This results in a resilient, distributed, asymmetric force that doesn't need to win at sea – it only needs to generate enough threat and uncertainty to prevent an adversary the freedom of action otherwise taken for granted.

The capabilities Iran has deployed illustrate this doctrine clearly. Autonomous vessels are controlled remotely, with a single operator able to direct multiple platforms at once. Underwater battery-powered vehicles patrol chokepoints for long periods, emitting acoustic signatures too small for conventional sonar to detect reliably in cluttered shallow-water environments. Networks of passive acoustic sensors offer ongoing subsurface awareness without needing a continuously staffed presence. Inexpensive mines force adversaries to carry out slow, dangerous, and resource-intensive mine-countermeasure operations. Faced with this, a sophisticated ‘traditional’ maritime power is faced with a fundamental cost asymmetry. A swarm of low-cost autonomous surface vessels can be fielded against a multi-billion-dollar destroyer. The economics of mass autonomous systems do not merely complement conventional military power; in the littoral they displace its fundamental logic.

The Convergence of Both Sides

What makes the current Hormuz situation so instructive is that both sides have drawn the same conclusions on autonomy simultaneously. The US’s Task Force 59 has been accelerating the integration of unmanned systems into its Middle East maritime operations since at least 2024. Prior to the current conflict, autonomous surface vessels have logged thousands of nautical miles of maritime patrols in operational areas, marking the US’s first sustained deployment of this approach in an operational environment. Mine-countermeasure operations are being carried out using autonomous surface platforms paired with semi-autonomous neutralisation systems, reducing the exposure of manned vessels and divers to a threat environment specifically designed to attrit them.

Both sides, in other words, have come to the same conclusion: the future of littoral warfare is autonomous, distributed, persistent, and cost-effective. Countries that understand this best – and develop the sovereign industrial base capable of supporting, scaling, and adapting this capability – will hold decisive advantage in every maritime chokepoint on earth. The question is not whether this change is occurring. It is who can bring it to bear fastest.

The Strategic Stakes

With roughly 20 percent of the world's traded oil passing through the Strait of Hormuz, we are seeing the impacts of that disruption extend far beyond energy prices. Iran, with a GDP about one-thirtieth of the United States, has caused significant disturbance to the global economy not through traditional military force, but through the clever, targeted use of inexpensive, autonomous, coastal-optimised systems.

The implications go well beyond the Persian Gulf. Every maritime chokepoint – the Malacca Strait, the Lombok Strait, the Torres Strait, the Sunda Strait – now falls under the same strategic logic. Any middle power with a coastline, a littoral setting, and the drive to build autonomous maritime capabilities can cause significant strategic effects against a more potent adversary. The challenge for nations responsible for these chokepoints is whether they are paying attention to what Iran has demonstrated – and whether they are developing the capabilities that allow them to learn from the lesson, rather than suffer from it.