China's AI Sea Mine Proposal Targets US Submarines Around the Paracel Islands

A proposed minefield beneath a disputed sea

Chinese military scientists have proposed using artificial intelligence to turn the waters around the Paracel Islands into a minefield designed to target US submarines. The plan, described in a peer-reviewed study by researchers from the People's Liberation Army (PLA) Dalian Naval Academy and Harbin Engineering University, would combine advanced sensors with underwater terrain to make the weapons harder to find.

As of September 1, 2025, the initiative is a research proposal. No deployment date is given. Its central idea is to place mines in acoustic shadow zones, areas behind submerged mountains and ridges where sonar has difficulty detecting objects. The weapons would remain dormant until their sensors identified a specific, approved target.

The Paracels are already heavily militarized. China has occupied the islands since 1974, while Vietnam and Taiwan also claim them. An intelligent minefield would add another layer to China's defenses in a disputed region where US forces regularly operate.

The proposal reaches beyond individual weapons. Researchers envisage mines working alongside seabed sonar, quantum sensors and groups of underwater drones. Together, these systems could detect, track and attack submarines moving through waters that China regards as essential to protecting its own nuclear forces.

For the United States, the concern is the combination of concealment and selective targeting. Its advantage beneath the sea depends heavily on submarines that can move quietly and remain difficult to locate. Mines positioned in sonar blind spots would create another danger for those vessels and another task for the forces responsible for clearing their routes.

How the mines would choose a target

Traditional sea mines can threaten any vessel that comes close enough to activate them. The Chinese proposal instead describes weapons intended to distinguish particular enemy vessels from other traffic before attacking.

Acoustic, magnetic and optical sensors would supply different kinds of information. Acoustic sensors listen for sound, magnetic sensors detect changes in magnetic fields, and optical sensors gather visual information. AI would help combine those signals and compare them with the characteristics of approved targets.

US submarines and other valuable naval vessels would be among the intended targets. A submarine's acoustic signature is its distinctive pattern of sound. The proposed system would listen for those patterns while using its other sensors to support identification.

The mines would also receive coatings intended to reduce their visibility to detection systems. Their concealment would therefore depend on both the weapons themselves and their placement. A mine hidden behind difficult terrain would present a different search problem from one lying in an exposed area of seabed.

Selectivity is central to the design: the weapons are intended to wait for designated vessels instead of reacting to every nearby ship. Their practical value would depend on reliable identification, dependable control and the ability to operate within a busy maritime environment.

Why underwater mountains matter

The seabed around the proposed operating area contains seamounts and ridges that affect how sound travels. Sonar uses sound to search underwater, but terrain can create places where its coverage is weakened. Chinese planners would use these acoustic shadows to conceal mines.

High resolution maps of seabed depth, known as bathymetric maps, would be combined with oceanographic data collected in real time. Researchers could then model sound propagation and identify positions where detection would be especially difficult.

Dr. Ma Benjun, an associate professor at Harbin Engineering University and a key figure in the study, described the intended advantage of selecting those locations:

By analyzing optimal deployment sites, we can improve concealment and make deployed assets much harder to detect. Such strategies could give China a significant tactical advantage in future undersea operations.

US Seawolf and Virginia-class nuclear submarines are among the exceptionally quiet vessels that underpin American undersea strength. The Chinese approach seeks to complicate their operations by making the surrounding environment more dangerous, even where the submarines themselves remain difficult to hear.

From isolated mines to a connected defense

Chinese researchers propose connecting the mines to a wider network for anti-submarine warfare, commonly shortened to ASW. Seabed sonar arrays, quantum sensors and swarms of underwater drones would contribute to the task of finding and tracking enemy submarines.

The proposed network would move beyond weapons waiting independently for a vessel to pass. Sensors and mobile systems could help locate an intruder, follow its movements and support an attack when required.

An analysis of the proposed mine network describes a move from passive defense toward active interdiction. In plain terms, that means moving from guarding an area to actively trying to stop an adversary from using it.

For US and allied submarine crews, a connected system would create several overlapping problems: avoiding detection, identifying dangerous areas and navigating around weapons that may be difficult to locate. For China, the attraction is a defense in which mines, fixed sensors and mobile drones support one another.

The same reliance on automated identification and connected systems also brings questions about reliability, control and unintended escalation. Those concerns become more pressing when weapons are placed in waters already used by competing military forces.

Why the Paracels occupy a central position

The Paracel Islands, called Xisha in China and Hoang Sa in Vietnam, are a chain of reefs and atolls about 300 nautical miles south of the Chinese mainland. Historically used by Chinese fishermen, they now contain airfields, ports capable of accommodating vessels with deep drafts, radar systems and permanent military garrisons.

Their location supports operations across the South China Sea, one of the world's busiest maritime routes. Nearly 500,000 merchant vessel passages take place in the region annually, giving any change in its security environment a commercial as well as a military dimension.

China's control remains contested by Vietnam and Taiwan. The United States regularly conducts freedom of navigation operations nearby, deploying surface vessels and submarines to challenge Chinese claims and demonstrate its commitment to keeping sea lanes open.

The chronology shows how longstanding territorial control now intersects with newer military technology:

• 1974: China began its occupation of the Paracel Islands, which Vietnam and Taiwan also claim.
• 2024: US submarine activity in the South China Sea increased, with at least 11 nuclear attack submarines, two submarines carrying guided missiles and one submarine carrying ballistic missiles operating in the region.
• September 1, 2025: The proposed AI minefield adds to discussion of how China could protect its forces and restrict opposing submarine operations.

The reported US presence in 2024 amounted to at least 14 submarines across those three categories. Their activities likely included following China's submarines armed with nuclear missiles, which provide the maritime part of its nuclear deterrent.

Protecting China's nuclear submarines

China's six Type 094 submarines carrying nuclear ballistic missiles are the centerpiece of its nuclear deterrent at sea. Each carries 12 submarine-launched ballistic missiles, giving the six vessels a combined capacity of 72 missiles. They conduct patrols on a near continuous basis in the South China Sea.

China uses a bastion strategy to protect these valuable vessels. A bastion is a defended area close to home where submarines can operate behind layers of military protection. Fortified islands and other military assets help shield the patrol area.

The mine proposal fits that approach. Weapons around the Paracels could make it harder for opposing submarines to enter or move freely through waters used by Chinese missile submarines. Protecting those vessels matters because their survival supports China's ability to threaten retaliation after a nuclear attack.

China's existing JL-2 missiles have limited range, constraining the areas its submarines can threaten from their home waters. Reaching positions farther into the Pacific would require the vessels to pass through narrow chokepoints where US and allied forces could intercept them.

China's missile submarines are also relatively noisy compared with their US counterparts, leaving them more exposed to advanced American underwater surveillance. Keeping them within a defended area provides protection but also makes their operating locations more predictable and potentially easier to target during a crisis.

The newer JL-3 missile is intended to reduce that geographic constraint by allowing Chinese submarines to strike the US mainland from within the South China Sea. Until that capability is fully realized, the relationship between missile range, patrol locations and submarine vulnerability remains a central weakness in the bastion strategy.

AI is also being used to reduce ships' magnetic signatures

The PLA Navy's interest in AI extends to protecting its own vessels from mines and detection. Recent naval exercises have used AI to assist decisions during degaussing, a process that reduces a ship's magnetic signature.

A vessel's magnetic field can help a sensor detect it or trigger a magnetic mine. Degaussing reduces that field, helping warships and submarines avoid those threats.

A naval degaussing drill report describes a 60 percent increase in efficiency through AI integration. The technology was used to improve the process of reducing a warship's magnetic field.

Faster, more accurate restoration of a vessel's reduced magnetic signature can improve its chances of surviving in a contested area. AI is expected to help select suitable algorithms and check the results in real time.

The mine proposal and the degaussing exercise address opposite sides of the same contest. China is exploring how to make weapons better at recognizing enemy vessels while also using automation to make its own ships harder to detect or attack.

Taiwan's mine defenses show the regional stakes

Taiwan has also invested in mine warfare as an asymmetric defense. That approach uses relatively inexpensive weapons to complicate operations by a larger force, particularly a possible PLA amphibious assault.

Taiwan's capabilities include automated systems for laying mines. The potential use of civilian vessels disguised for military purposes would add another complication to identifying where mines had been placed.

A translation and analysis by the China Maritime Studies Institute describes how Taiwanese minefields could obstruct PLA landing operations, limit fleet movement and leave ships more vulnerable to missile attacks. Clearing a passage would consume time and resources.

Delays would matter during an invasion. Time spent searching for and removing mines could slow the arrival of troops and equipment while giving Taiwan more opportunity to receive outside support.

China's proposed intelligent mines pursue the same basic military benefit of denying an opponent freedom of movement, with added emphasis on selective targeting, concealment and connections to other sensors. Across the region, mine warfare offers a way to impose difficult choices on forces that depend on access to particular waters.

Open sea lanes and competing military claims

The South China Sea remains a legal and diplomatic contest as well as a military one. Vietnam, the Philippines and Malaysia maintain claims and outposts in the region, while China has extensively militarized artificial islands and reefs.

A report by the South China Sea Strategic Situation Probing Initiative (SCSPI) found that China had not imposed explicit restrictions on foreign military ships and aircraft outside its territorial seas and airspace. It described a region still highly open to economic trade and military activity.

The report recorded more than 20,000 ship-days and over 30,000 aircraft sorties annually. A ship-day represents one ship operating for one day, while a sortie is an individual aircraft mission. Those measures show the scale of activity in the region.

SCSPI argued that most interactions between Chinese and US forces were professional and safe. Friction nevertheless occurred near sensitive locations, particularly during exercises and close encounters.

AI mines would introduce weapons capable of making automated targeting decisions into that environment. A mistaken identification or an encounter near a concealed minefield could make an already tense confrontation harder to manage.

The Philippines has acquired BrahMos supersonic cruise missiles from India, with the ability to target Chinese positions such as Scarborough Shoal. Those weapons, alongside competing claims and military operations, help shape China's decisions about how far to strengthen its hold on disputed areas.

How US and allied operations could change

The US Navy uses regular freedom of navigation operations to contest Chinese claims and maintain access to sea lanes. A concealed mine network could complicate those missions, requiring changes in tactics for both surface vessels and submarines.

Mine countermeasures would become more demanding where weapons were hidden in difficult terrain and linked to outside sensors. Persistent surveillance, drones and technologies for detecting and clearing mines would therefore take on a larger role.

Atlantic Council experts have warned that China's broader maritime strategy includes autonomous systems, drones and weapons covertly positioned in advance at overseas ports. Their assessment extends the access problem beyond the Paracels to ports and bases that could support Chinese operations elsewhere.

A US response would likely include joint operations, new tactics for seizing ports, broader use of drones and investment in continuing surveillance and mine clearance. Planning and training would also be needed to prepare forces for operating around those threats.

China's use of overseas ports and bases presents another challenge alongside its defenses closer to home. US and allied adaptation would depend on combining new equipment with procedures for finding concealed weapons and maintaining access during a crisis.

The northern gap in China's bastion

China's proposed underwater defenses would still sit within an incomplete bastion. The absence of a northern outpost, such as a fortified position at Scarborough Shoal, leaves a gap in its strategic triangle that US and allied forces could exploit.

Frequent US and Philippine operations near Scarborough Shoal, together with advanced missile deployments, may discourage China from fully fortifying that position. A stronger mine defense around the Paracels would therefore coexist with vulnerability elsewhere.

The gap matters in a possible conflict over Taiwan. If China cannot reliably protect its submarines carrying nuclear missiles, those vessels may provide a less dependable backstop against US and allied intervention.

AI mines could improve concealment and make opposing submarine operations more hazardous. China's broader problem still involves protecting patrol areas, managing access routes, extending missile reach and maintaining reliable control over automated weapons in a region crowded with competing forces.

Key Points

• Researchers from the PLA Dalian Naval Academy and Harbin Engineering University propose AI mines around the disputed Paracel Islands.
• The weapons would combine acoustic, magnetic and optical sensors to identify approved targets and hide in sonar blind spots.
• The proposed network would include seabed sonar, quantum sensors and underwater drones.
• China's six Type 094 submarines each carry 12 ballistic missiles and depend on a defended patrol area in the South China Sea.
• Missile range, submarine noise and an exposed northern flank complicate China's bastion strategy.
• A PLA Navy exercise reported a 60 percent efficiency improvement when AI assisted degaussing.
• Taiwan's mine defenses, Philippine missile purchases and US operations form part of the wider regional contest.
• The mine initiative remains a proposal as of September 1, 2025, with reliability, control and escalation among the central concerns.