China's seabed survey campaign around Taiwan has crossed into operational battlespace preparation, and the corridors Beijing chose to map confirm it. The Times reported this week that PLA Navy survey vessels have concentrated bathymetric work on the Bashi Channel, Taiwan's southern approach, and the straits northeast of the main island. Civilian navigation does not require that geometry. Submarine approach-lane optimization does. Asia Times reported separately on a PLA naval railgun calibrated for Taiwan-side targets. The programs are separate. The kill-chain geometry is not.

The US Senate passed a $2 billion security assistance package for Taiwan and the Philippines this week, covering air defense batteries and naval surface platforms. Taiwan's underwater order of battle is two Hai Lung-class diesel submarines, Dutch-built and commissioned in 1988, plus Hai Kun (SS-711), the first indigenous hull, launched at CSBC Corporation's Kaohsiung yard in September 2023, with sea trials running into 2026. Three hulls total. Against a PLA force that has now surveyed the Bashi Channel in bathymetric detail, those three hulls are the entire asset pool available to contest the approach lanes Beijing spent the last two years mapping. The Senate package as passed funds zero anti-submarine warfare systems.