Why did the US Navy fit the 25 mm Bushmaster to its ships?
Short answerIt provides effective small-boat defense and benefits from an existing, well-understood logistics and support chain.
NotesThe first purpose given for the 25 mm Bushmaster is defense against small boats. Another participant also mentions aircraft. An existing weapon brings an established logistics system and known operating characteristics, which explains part of its appeal. The final comment values human operation because it avoids unexpected behavior associated here with automatic close-in systems. The passage does not specify engagement ranges or a particular control-system variant.