According to reports, China’s People’s Liberation Army Navy (PLAN) could use large underwater drones to lay mines to blockade the “First Island Chain” should tensions over Taiwan escalate.

Suggested in a Chinese military magazine, Shipborne Weapons, the strategy would likely see the use of China’s large AJX002, long-range (perhaps 1.118-mile/1,800 km) minelaying underwater drone, first seen at a recent military parade in Beijing.

Under such a strategy, the PLA would use the drones for “offensive minelaying” missions targeting Japan’s islands, including the Ryukyu archipelago. Other targets could include the waters of the Philippines.

This, the South China Morning Post (SCMP), the idea may well have been inspired by recent activities in the Strait of Hormuz, which showed how vulnerable strategic waterways can be to blockades of this nature.

In case you are unaware, the “First Island Chain” is a line of islands in the Pacific that runs from Japan, past Taiwan, down to the Philippines. It is seen by the United States and its allies as an effective geographic line that could be used to box in China’s navy from the wider ocean.

PLA floats minelaying drone strategy

If tensions over Taiwan were to become hot, then control of this chain would be vital to ensure that trade routes are kept open. It would be vital to protect US (and ally) military movements and logistics supply.

Any action on either side to blockade this chain would prove detrimental to both naval and commercial traffic in the region. And so, PLAN logic goes, the use of uncrewed (autonomous) drones could prove a game-changer, for obvious reasons.

Drones like the AJX002 are large torpedo-shaped vessels specifically designed to carry payloads of naval mines. They are relatively silent, smaller than a submarine, and can infiltrate sea lanes stealthily.

Once in place, they can deploy mines without the risk of losing a human crew should the drone be discovered and destroyed. If successful, however, sea mines are able to sit in the water and detonate when a ship passes by.

For this reason, they have historically been a very effective way to deny safe passage through a body of water. Modern sea mines are far more sophisticated than this, and can be “programmed” to only trigger when a certain ship type comes close.

As for the PLAN’s mention of “offensive minelaying,” this refers to the deployment of mines in enemy waters rather than a nation’s own. So, in the sense of Taiwan, that would see mines deployed in shipping lanes near Japan, access routes in the Philippines, and other chokepoints within the “First Island Chain.”

A double-edged sword

Such an action would make it difficult for US and allied ships to safely navigate these waters. It would also dramatically disrupt Japanese and Philippine commercial shipping, ultimately impacting their economies.

This is not only costly in terms of lost trade, but mines are also not quick to clear up. Mine clearing is a laborious and time-consuming process fraught with danger.

Even if cleared, confidence in using the same shipping routes can take time to recover. Clearly, commercial shipping companies (specifically their insurers) will be hesitant to return to normality.

But, while effective, mine-laying operations of this kind would not be “risk-free” for China. Mining international, nominally neutral waters, risks escalating any conflict massively.

It would also impact Chinese trade, perhaps seeing large-scale sanctions or embargoes that could backfire on Beijing in the long run.