75 Years Later, Remembering the Battle of the Coral Sea

America’s involvement in World War II was so massive that it’s easy to forget lesser-known battles, especially those in the Pacific Theater of Operations. But every success, and even loss, contributed to a refinement of the Allied strategy to defeat the Germans and Japanese. The Battle of the Coral Sea in May 1942 was no exception.

Beginning in December 1941, the Japanese had devastated the U.S. Fleet at Pearl Harbor, seized Hong Kong, conquered Southeast Asia, the Dutch East Indies and much of the Philippines, and terrorized the Indian Ocean with a naval sweep. Singapore had surrendered, and Bataan fell. The Allies had suffered major losses at sea and in the air by early May 1942. While the tiny U.S. garrison at Corregidor in Manila Bay still held out, its days were numbered. Everywhere the Japanese were victorious. The Allies faced their darkest hour.

Beginning on May 4, 1942 the U.S. Navy and its Australian allies, under the command of American Rear Adm. Frank J. Fletcher, began battling the Imperial Japanese Navy across the breadth of the Coral Sea. Located northeast of Australia and southeast of Papua New Guinea, the Japanese understood that total control of the Coral Sea could cripple Allied communication in the Pacific and cut off the supply route between the United States and Australia.

Prior to this battle, Japanese advances through the Pacific archipelagos had leap-frogged, flying planes from bases just captured to support assaults on the next set of targets. The Japanese resolved to seize Tulagi in the Solomon Islands and Port Moresby in New Guinea in order to cut off vital strategic communication channels that connected the United States and Australia. The Japanese had planned for  heavily escorted convoys to steam in from the west to conduct these amphibious assaults. Meanwhile a Japanese carrier force would swing around the Solomon Islands to enter the Coral Sea from the east, hoping to come in behind and trap Allied naval forces that dared to interfere. 

The U.S. Navy ascertained the broad outlines of the Japanese plan through signals intelligence, and resolved to contest it. All told the Allies and Japanese had gathered remarkably similar fleets, making the battle odds nearly even in terms of ships and aircraft involved.  

Stung by the Doolittle Raid of April 18, in which American aircraft bombed Tokyo, the Japanese assumed that all or most American carriers were in the Central Pacific.  American aircraft from the USS Yorktown surprised the Tulagi landing force on May 4, sinking a destroyer and three minesweepers, and damaging four other ships.  Fletcher, covered by an overcast sky, then maneuvered between the Port Moresby invasion force and the main Japanese carrier force. On May 7 he struck the invasion force, sinking the light carrier Shōhō. Meanwhile the Japanese searched for and missed Fletcher’s main force, but did sink a destroyer and mortally damage an oiler. Aviators from both sides strained to find each other’s ships over vast distances.

On May 8  the overcast sky covered the Japanese rather than the Americans. Japanese bombers and torpedo planes severely damaged the USS Yorktown and USS Lexington, the latter so badly that it was eventually scuttled. One Japanese carrier was severely damaged, while the other lost most of its aircraft. Stripped of air cover and having been attacked by land-based bombers as well as Fletcher’s naval aviators, the Japanese Port Moresby invasion force withdrew to Rabaul, a port on an outlying New Guinea island. Fletcher pulled out of the Coral Sea as well, having received orders to speed to Hawaii with the Yorktown. Most of his surface vessels continued to cover Australia. The Japanese carrier task force, down one carrier and most of its planes, remained in the Coral Sea long enough to ascertain that the Americans had withdrawn, then withdrew themselves. In the Battle of the Coral Sea, naval air power assumed an unprecedented role, with ship-killing blows delivered by air while surface contingents never saw each other. After four days of confused fighting, the Japanese claimed a tactical victory. They were arguably correct but, far more important, they had suffered a strategic defeat. After five months of breath-taking advances, the Japanese juggernaut had at last been arrested.

Their two damaged Japanese carriers withdrew to Kure, Japan, for repair and refurbishment. They were not again available for combat until July 14, and thus missed the decisive Battle of Midway (June 4-7, 1942). The Yorktown, on the other hand, sped to Hawaii, was refurbished within 48 hours, and played a crucial role at Midway. Japanese defeats at Port Moresby, Midway and, subsequently, Guadalcanal marked a critical turning point in the Pacific War. The Battle of the Coral Sea proved to be a consequential prelude to them all.

Recommended Reading

Henry, Chris, The Battle of the Coral Sea (Annapolis, Maryland: Naval Institute Press, 2003)

Morison, Samuel Eliot, Coral Sea, Midway and Submarine Actions, May 1942 - August 1942 (Champaign, Illinois: University of Illinois Press, 2001 (reprint of 1949 edition))

Spector, Ronald H., Eagle Against the Sun: The American War with Japan (New York: The Free Press, 1985)