Why Japan pursued floatplane fighters more seriously

Why did Japan field a floatplane Zero fighter when British and American float-equipped fighters remained experimental?

Japan needed fighters independent of vulnerable carriers and airfields, while Britain and America could rely on more surviving conventional bases.

The explanation offered for Japan's stronger interest in floatplane fighters is its need to move fighter cover after losing carriers and air bases. A float-equipped Zero could provide an alternative where those facilities were unavailable. Britain and the United States are contrasted as retaining more conventional operating facilities. A separate technical concern is the Spitfire's lack of navalization: fitting floats alone would not protect it against corrosion. This operational-use comparison does not establish a detailed chronology of the aircraft programmes.