Port Moresby, Papua New Guinea May 4, 1942

On this date in 1942 the five-day Battle of the Coral Sea began. A Japa­nese inva­sion fleet of five troop trans­ports and seven destroyers from their bastion of Rabaul on the island of New Britain, in con­cert with a Japa­nese carrier force from Truk (Chuuk) in the Central Pacific, was steaming toward the capital of Aus­tra­lian Papua New Guinea, Port Moresby, which had the poten­tial of becoming, after Rabaul’s auda­cious cap­ture ear­lier in Janu­ary, another major Japa­nese staging point and air base in the South Pacific (see dotted line on map below). If the Japa­nese gained an advance base in Papua New Guinea, they would strengthen their defen­sive posi­tion and sever the U.S. West Coast-Hawaii-Aus­tralia life­line, and their air­craft would be within striking dis­tance (1,124 miles) of Darwin, Northern Australia, a strategic port and air base for the Allies.

Naval and air force units from the United States and Aus­tra­lia, under the over­all com­mand of Amer­i­can Rear Adm. Frank J. Fletcher, set out to stop the Japa­nese. The resulting engage­ment south­west of the Solo­mon Islands was the first of five car­rier ver­sus car­rier sea battles in naval history and the first naval battle in which two opposing fleets were never in visu­al con­tact. Sepa­rated by 175 miles of ocean, the fleets battled each other with their carrier air­craft. The losses were about equal on both sides: the U.S. lost its first carrier of the war, the 888-ft-long fleet car­rier Lexing­ton, Japan the heavy cruiser Mikuma and the light carrier Shōhō, the first enemy carrier to be sunk in combat. Still, it was the first time the Japa­nese had expe­ri­enced failure in a major oper­a­tion. That in itself gave the Amer­i­cans a huge morale boost following the inev­i­table loss of the last U.S. garri­son, Correg­idor (May 5–6, 1942), in enemy-held Philip­pines. Further­more, the damage the Allies inflicted on the big Japa­nese fleet carriers Shōkaku and Zuikaku pre­vented the sister flat­tops from par­ti­ci­pa­ting in the Battle of Midway the following month (June 4–7, 1942). That pivo­tal battle was a clear-cut vic­tory for the U.S. Navy, and the ini­ti­a­tive, both at sea and in the air, now lay squarely with the Americans.

But not on land. The Japanese still attempted to take Port Moresby, viewed as a threat to their naval and ground opera­tions in the Bis­marck and Solo­mon Seas, via the moun­tain­ous Kokoda Track (July 1942 to Janu­ary 1943), staging from Buna and Gona on the north­east coast of the island. During the New Gui­nea cam­paign (January 1942 to August 1945), more than 33,000 Amer­i­cans and Aus­tra­lians fought the Japa­nese, suffering a casualty rate of 1 in 11. The U.S. 2nd Bat­talion/­126th Infan­try Regi­ment (nick­named “Ghost Bat­talion”) was espe­cially hard hit. Out of 1,400 men who went into action on Novem­ber 21, 1942, only six officers and 126 troops were standing when Buna was retaken six weeks later. By com­par­i­son, 60,000 Amer­i­cans fought the Japa­nese on Guadal­canal in the Solomon Islands (August 7, 1942, to February 9, 1943), where 1 in 37 GIs died.

Sea and Land Campaigns in the Southwest Pacific, 1942–1943

Port Moresby Invasion/Battle of Coral Sea

Above: Map showing the movements of the Japanese Port Mores­by sea­borne assault force (dashed lines in center) and the plan for the force’s landing (bottom left corner), which the Japa­nese called “Opera­tion Mo.” The sinking of the light carrier Shōhō, which took 600 of her 800 crew­men to their graves, together with the battering the carrier Shōkaku received prompted the Japa­nese to recall the Port Mores­by inva­sion force back to its starting point, Rabaul. Port Mores­by, on the south­eastern coast of the Papuan Penin­sula of the island of New Guinea, was the last Allied base between Aus­tra­lia and Japan. The map also depicts the naval Battle of the Coral Sea, May 4–8, 1942 (solid lines in right half). With Japan’s failure to capture Port Mores­by, the invasion threat to Northern Australia disappeared.

USS Lexington, May 8, 1942Girau River, Buna, New Guinea, 1942

Left: U.S. fleet carrier Lexington burning after her crew aban­doned ship during the Battle of the Coral Sea, May 8, 1942. Some 216 crew­men were killed and 2,735 evacuated. The “Lady Lex” sus­tained numer­ous hits from Japa­nese carrier air­craft. How­ever, it was a series of massive explo­sions initially set off by sparks that ignited gaso­line vapors from ruptured fuel tanks that proved fatal to the flat­top. The Lexing­ton was sent to the ocean floor after Rear Adm. Fletcher ordered a U.S. destroyer to torpedo the flaming wreck.

Right: Three members of the U.S. 32nd Infantry Division move supplies by boat on the Girau River on New Guinea’s north­east coast near enemy-held Buna Mission sometime in late 1942. (The 32nd was the first com­plete Amer­i­can divi­sion, con­sisting of 12,000 men and equip­ment, to reach the South­west Pacific Area.) The jungle was so thick that “in the dark, live Amer­i­cans bumped into live Japs,” wrote combat photo­jour­nalist George Strock for LIFE magazine, while day­light would reveal “dead Amer­i­cans . . . along­side dead Japs.” With no roads through the jungle-clad island, the only way to keep Allied troops fur­nished with the food, am­mu­ni­tion, and other goods neces­sary to oper­ate against the Japanese was via water and airborne supply.

Dead GIs on Buna Beach, February 1943Australians attack near Buna, January 1943

Left: Three GIs lie dead on Buna Beach near a wrecked landing craft. This image by LIFE magazine’s George Strock taken in Febru­ary 1943 was not pub­lished until Septem­ber 20, 1943, when Presi­dent Franklin D. Roose­velt autho­rized its release, the first image to depict Amer­i­can sol­diers dead on a battle­field. (U.S. mili­tary censors placed no restric­tions on photos of enemy war dead.) FDR was con­cerned that the pub­lic was growing com­pla­cent about the cost of the war on American lives.

Right: Australian forces attack Japanese positions near Buna, Janu­ary 7, 1943. Members of the 2/12th Infantry Battalion advance as Stuart tanks from the 2nd Bat­talion/6th Armored Regi­ment attack Japan­ese pill­boxes. An upward-firing machine gun on the tank sprays treetops to clear them of snipers.

Battle of the Coral Sea, May 4–8, 1942: An Australian Tribute