The Battle of the Coral Sea, the first naval battle in which the participating ships never came in sight of each other, ended.
The Coral Sea is situated off the northeast coast of Australia. Following Japan’s entry into the Second World War, the Imperial Japanese Navy sought to establish perimeter defences in the region to protect the Japanese empire and isolate Australia and New Zealand from their ally the United States.
Japanese forces launched Operation MO, in which they planned to seize Port Moresby in New Guinea and Tulagi in the Solomon Islands, on 3 May 1942. However, the Allies had intercepted messages about the impending attack and launched a series of surprise airstrikes against the Japanese from the U.S. fleet carrier Yorktown.
The Allied attack failed to stop the Japanese landings on Tulagi, but caused significant damage to the fleet that reduced its effectiveness in the second stage of the plan. Clearly aware of the presence of enemy aircraft carriers in the area, the Japanese consequently sought to locate and destroy the allied naval forces.
On the morning of 7 May, Japanese carrier-based planes located and sank a U.S. destroyer and an oiler while American planes sank the light Japanese carrier Shōhō and a cruiser. The following day Japanese aircraft damaged the U.S. carriers Yorktown and Lexington, which was later scuttled. Meanwhile the Japanese carrier Shōkaku was heavily damaged and had to withdraw, while Zuikaku suffered large aircraft losses that excluded it from the Battle of Midway the following month. Consequently while Japan experienced a tactical victory in terms of the number of ships sunk, the Allies gained a strategic advantage as Japan was forced to abandon Operation MO.