Concentrating every investment on submarines, drones, aircraft, or surface ships presents an opponent with a narrow problem to solve. A navy can emphasize one capability while retaining alternatives that threaten defenses built against its main strength. An enemy that concentrates too heavily on that strength then exposes itself to the rest of the fleet. Keeping that wider range forces the opponent to maintain broader capabilities and makes its own force-design choices harder.
Notable Point · 4:04-5:07
A broad fleet complicates an opponent's priorities
Retaining several kinds of naval capability forces an enemy to spread its attention even when one part of the fleet receives greater emphasis.