National destroyer solutions and the six-inch cruiser

National destroyer designs reflected different compromises. American and Japanese large destroyers concentrated heavily on torpedoes, while the Royal Navy added more destroyer guns without losing sight of the torpedo role. French and Italian ships occupied the space between very large destroyers and very small cruisers. They suited Mediterranean conditions, though the discussion raises doubts about their behaviour in rougher seas beyond that theatre. The Royal Navy's preference for six-inch cruisers followed a related calculation: six-inch guns could fight another cruiser without the weight penalty of an eight-inch battery, leaving more displacement for protection.