What was the Coral Sea battle?

The Coral Sea battle was a naval engagement fought between Allied forces (primarily American, with Australian support) and Imperial Japanese Navy forces in the Coral Sea off the north-east coast of Queensland from 4 to 8 May 1942. It was the first naval battle in history fought entirely between aircraft launched from carriers, with no surface ship of either side firing on the other. The battle stopped the Japanese advance toward Port Moresby in Papua and is widely cited as the moment the Japanese southward advance was first halted.

The Japanese strategy in early 1942 included Operation MO, the seaborne invasion of Port Moresby to threaten Australia. A Japanese invasion force of 11 transports, escort warships, and the carriers Shokaku, Zuikaku, and the light carrier Shoho departed Rabaul on 30 April 1942. Allied intelligence had broken the Japanese naval code and predicted the operation, so US carriers Lexington and Yorktown (plus Australian and US cruisers and destroyers including HMAS Australia and HMAS Hobart) were deployed to intercept.

The main carrier engagements took place on 7 and 8 May 1942. The Allied force sank the light carrier Shoho on 7 May (the radio call 'Scratch one flat-top' from US Lieutenant Commander Robert E. Dixon entered American naval folklore). On 8 May, simultaneous air attacks were made by both sides. The Japanese carriers Shokaku and Zuikaku were damaged but survived. The American carrier Lexington was hit by torpedoes and bombs, was eventually abandoned, and sank that evening. The Yorktown was damaged but stayed afloat. Tactically the battle was broadly a draw (with the Americans losing more tonnage), but strategically the Allies won: the Japanese cancelled the Port Moresby invasion and withdrew.

The Coral Sea battle had wider consequences. The damage to Shokaku and Zuikaku and the loss of their experienced pilots kept both carriers out of the Battle of Midway one month later (4 to 7 June 1942), which decisively turned the Pacific War. The cancellation of the Port Moresby seaborne invasion led the Japanese to attempt a land advance over the Owen Stanley Range via the Kokoda Track, which the Australians stopped from July to November 1942. The Coral Sea is commemorated each year on Coral Sea Day (8 May) at the Australian War Memorial and at various naval bases. The battle is also commemorated jointly by Australia and the United States and marks the moment of close Australian-American cooperation that underpinned the post-war ANZUS alliance. The 1942 to 2022 80th anniversary marked the close Australian-American commitment that continues through the AUKUS partnership.