Japan was already at war in China by 1940, following the conflict's expansion in 1937. Although the Imperial Japanese Army led much of the campaign, the Imperial Japanese Navy was not a detached spectator. Naval forces conducted fleet operations and supplied air support for fighting ashore, giving naval aviation combat experience before the Pacific War. Prewar Japanese naval planning therefore cannot be separated from the navy's active participation in the Second Sino-Japanese War.
Notable Point · 37:18-37:48
The Imperial Japanese Navy's active war in China
Japan's navy was already providing air support and fleet operations in China before the wider Pacific War.