Converted fast cruisers and the scale of carrier investment

Fisher's fast 'greyhound' cruisers were intended to hunt commerce raiders, and their speed later suited carrier work. Furious, Courageous, and Glorious underwent unusually extensive conversions; Eagle also became a carrier from a battleship design. Their large-light-cruiser origins may have influenced how some naval officers regarded and employed Courageous and Glorious. More advanced Hood-class construction might instead have yielded two larger carrier conversions. Britain, Japan, and the United States spent heavily on carriers during a period when treaties suppressed new battleship construction. France and Italy left much of their allowance unused, and Italy did not begin the Aquila conversion until the Second World War was already underway. Treaty permission alone did not create a carrier force.