Japanese planners could identify and concentrate against ships permanently based on the China Station. Town-class cruisers in the Indian Ocean were harder to locate and could move toward Singapore when a crisis developed. Any Japanese surface force entering the ocean would first have to pass the British position at Singapore. The cruisers therefore served as both a rapid-reaction force and a deterrent that did not require the whole fleet to sit exposed at the forward base.
Notable Point · 18:52-20:28
Town-class cruisers as a mobile Far East deterrent
Cruisers held in the Indian Ocean could reinforce Singapore without presenting Japan with a concentrated force to watch or overwhelm in harbour.