How underwater drones are threatening to escalate South China Sea tensions

On April 15, American defence secretary Ashton Carter announced that the US is on the verge of deploying “new undersea drones in multiple sizes and diverse payloads that can, importantly, operate in shallow water where manned submersibles cannot”. He chose his visit to the US aircraft carrier Stennis, sailing in the South China Sea, to make the announcement, thus sending a clear message to China.

The initial role of the unmanned underwater vehicles is likely to be intelligence, surveillance and reconnaissance. But they could also be used to track “enemy” submarines and even launch missiles and unmanned aerial vehicles. Such drones could easily enter territorial seas and even harbours undetected. Amid tightening tensions in the South China Sea, this technological “threat” raises controversial legal and political questions surrounding their use. Indeed, the proliferation of drones and their roles create conflicts with the 1982 UN Convention on the Law of the Sea.

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These developments will clearly complicate the already strained US-China relationship regarding surveillance activities in the South China Sea. That relationship has already been sorely tested by the EP-3 (2001), the Bowditch (2001), the Impeccable (2009), the Cowpens (2013) and the Poseidon (2014) encounters. These incidents all involved Chinese challenges to US naval surveillance vessels and aircraft undertaking missions in its 200-nautical-mile exclusive economic zone that China perceived to be a threat to its security.

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China and the US have converging strategic trajectories. China is developing what the US calls an “area denial strategy” designed to control China’s “near seas” and prevent access by the US in the event of a conflict – say between China and Taiwan. The US response is the air-sea battle concept, which is intended to cripple China’s command, control, communications, computer and intelligence, surveillance and reconnaissance systems. This is the “tip of the spear” for both, and both are trying to dominate this sphere over, on and under China’s near seas. For both, drones are becoming the tip of that tip.