At the Shangri-La Dialogue in Singapore, Australian Defence Minister Richard Marles issued a stark warning that the “seabed is becoming a battlefield.” Speaking at Asia’s largest defence summit, Marles highlighted a documented pattern of attacks against critical subsea infrastructure, describing undersea internet cables as the “arteries of modern civilisation.”
A New Frontier in Underwater Defense
In response to these growing threats, the US, UK and Australia have announced a new Aukus project focused on developing underwater drone technology. This initiative aims to create a suite of highly adaptable, multi-mission uncrewed underwater vessel (UUV) payloads designed to protect vital undersea cables.
UK Defence Secretary John Healey noted that these cutting-edge sensors and weapons systems will provide forces with advanced battlefield technologies. This development follows the decision that Australia will purchase three secondhand Virginia-class submarines from the US under the Aukus treaty. This move is intended to simplify supply chain management and maintenance requirements while maximising cost efficiencies.
Geopolitical Tensions and the ‘Shadow Fleet’
Marles expressed concern over the vulnerability of island nations, noting that cables can be “cut with an anchor in the middle of the night.” He cited five instances of cables being cut in the Taiwan Strait over the last 18 months, attributed to China, and three in the Baltic Sea, alleged to be committed by Russia.
The Minister also targeted the “shadow fleet”—unregistered vessels operating in the “grey zone” between commercial shipping and state coercion. These networks, he argued, serve as vectors for illegal fishing, drug trafficking, and the transport of energy that sustains Russia’s war in Europe.
US Commitment and Regional Stability
US Secretary of Defence Pete Hegseth reinforced the US stance, stating the administration would not allow China to dominate the Pacific. While Hegseth did not directly mention Taiwan, he emphasized the US desire for “partners, not protectorates” and spoke of creating a “stable equilibrium” in the region.
Hegseth also highlighted a record US$1.5tn defence budget request, which he claimed would expand American military dominance for decades. This comes amid growing concern in Taiwan regarding the robustness of US commitments to the island, following a recent summit between Donald Trump and Xi Jinping.
Looking Ahead
The deployment of new UUV technologies could potentially enhance the ability of allies to monitor and protect vulnerable maritime domains. As the US pursues a larger defence budget, the military presence in the Asia-Pacific may increase, which could impact the regional balance of power.
the continued use of “grey zone” tactics by shadow fleets and maritime actors may continue to test the attribution thresholds and political will of international powers. The interaction between these new technologies and existing maritime patterns is likely to remain a central focus for regional security.
Frequently Asked Questions
What is the primary goal of the new Aukus project mentioned?
The project aims to develop new underwater drone technology, specifically multi-mission UUV payloads, to protect undersea cables and maintain a maritime advantage.
Why is Australia purchasing secondhand Virginia-class submarines?
The decision to buy three secondhand submarines instead of a mix of old and new is intended to simplify supply chain management, operational requirements, and maintenance while maximising cost efficiencies.
What did Richard Marles say about the vulnerability of subsea cables?
Marles stated that critical infrastructure, including financial and health systems, is critically dependent on cables that are exposed and can be cut easily, making island nations acutely vulnerable.
How should nations balance economic reliance on global infrastructure with the need for heightened maritime security?
