While this doesn't stop American (and allied) freedom of navigation operations in the South China Sea, this surveillance net will make operating there in wartime for any Chinese enemy difficult:
China has begun building a multi-sensor system for obtaining constant data on the precise location of surface and submarine vessels in the South China Sea. Surface surveillance would be carried out by a constellation of ten remote sensing satellites so that the South China Sea is under constant surveillance. ...
To make this surveillance system work China is using or adapting a lot of existing technologies. For underwater surveillance China is installing a network of underwater sensors similar to the American Cold War era American SOSUS (SOund Surveillance System).
Strategypage notes that by 2030 the Chinese will have 30 percent more warships than the American Navy.
America will have allies with good navies to help us. China will be able to concentrate their own navy with nearby shore-based air and missile support while America's navy is scattered across the globe.
