China's New Drone Mothership Targets US Undersea Edge

Notably, the US and Japan operate the“Fish Hook” underwater sensor network, spanning Japan, Taiwan, the Philippines and Indonesia, to detect any Chinese submarine movement attempting to break out into the open waters of the Pacific.

However, Ryan Martinson, in a June 2025 Center for International Maritime Security (CIMSEC) article, notes that such a breakout carries staggering detection risks, severely compromising their operational stealth and strategic nuclear deterrence.

Citing People's Liberation Army Navy (PLAN) sources, Martinson says that the US Navy's integrated, three-dimensional surveillance architecture-spanning fixed seabed sonar, ocean surveillance ships, aircraft, and orbital satellites-creates an“extremely high” probability of tracking Chinese submarines directly upon leaving port.

He also notes that PLAN sources acknowledge a“fairly high” probability of detection and interception while navigating Near Seas transit corridors, with US hydrographic and acoustic nets blanketing critical choke points.

Still, Martinson notes that according to PLAN sources, the US lacks sufficient forces to cover the East and South China Seas, and that nodes in the US sensor network could be destroyed.

In line with that, Chris O'Flaherty notes in a July 2025 article for The Strategist that China could destroy US undersea sensors in several ways, either overtly by deploying a drone mothership that launches UUVs to sever underwater cables, or covertly by UUVs planting explosive charges near underwater cables long before hostilities begin, to be detonated later by a coded acoustic signal.

O'Flaherty also adds that cable repair ships such as the USNS Zeus – the only one the US has – are easy targets.

David Axe points out in the same article that while the US could deploy the USS Jimmy Carter special mission submarine to repair damaged underwater cables, the US Navy would still be stretched thin protecting the underwater network that gives it one of its greatest wartime advantages.

Axe adds that while private companies have cable repair ships, fewer than 10 exist out of a required global fleet of 20, and private companies may not be willing to risk their ships operating in a conflict area.

Defensively, Chinese planners are considering how XLUUVs integrated into a wider maritime sensor network can systematically eliminate longstanding US advantages in submarine stealth.

Underscoring that point, Peter Sullivan mentions in a July 2026 National Security Data and Policy Institute (NSDPI) report that China is eroding US undersea superiority across the Pacific by fielding an unmatched fleet of Extra Large Unmanned Underwater Vehicles (XLUUVs) integrated into its emerging Transparent Ocean strategy.

In an October 2025 Defense One article, Tye Graham and Peter Singer say China's Transparent Ocean strategy is an integrated, five-layer sensor architecture spanning seabed to space, designed to eliminate hiding spots for US and allied submarines across the Western Pacific.

As Graham and Singer explain, the strategy centers on constructing a resilient, automated“kill web” that links orbital lidar and radar satellites with surface buoys, water-column gliders, and cabled seafloor observatories that power and dock autonomous submersibles.

They observe that oceanographic and acoustic data are synchronized through the“Deep Blue Brain” fusion hub to compute dynamic strike routes in real time.

In detailing this architecture, Graham and Singer emphasize that bypassing traditional single-point failure chains allows China to maintain persistent tracking nets across vital maritime choke points.

Persistent US submarine operations along China's maritime periphery may underscore the urgency of developing such capabilities.

According to a June 2026 report by the South China Sea Probing Initiative (SCSPI), a Chinese think tank, the US operated at least 11 nuclear-powered attack submarines (SSNs)-including the USS Seawolf, USS Asheville, and USS Greeneville-alongside the guided-missile submarine (SSGN) USS Ohio across the Western Pacific theater in 2025.