Maybe someone will do a subsurface nuc-burst causing a wave to wipe out each of Chi-com Suzi's illegal islands. Then the USMC can go in and render aid to survivors and plant the US Flag.
1 SSN could basically wipe out every single Chinese atoll with a barrage of cruise missiles. So these bases are essentially pawns on the Pacific chessboard. Not very useful when a shooting war breaks out. But then this is about controlling resources and shippie lanes.