Text and web-site by James Bowen. Last updated 8 October 2009

The apparently inexorable advance of Japanese military forces across the Pacific and South-East Asia forced President Roosevelt to replace senior American navy and army commanders in the Pacific region who had failed to heed warnings from Washington and take appropriate steps to meet the Japanese threat to their commands. The navy and army commanders at Pearl Harbor at the time of the Japanese attack were replaced. General Douglas MacArthur escaped dismissal because the full story of his incompetent defence of the Philippines was not revealed until after the war. The Chief of Naval Operations in Washington, Admiral Harold R. Stark, was replaced as Commander in Chief of the US Navy by Admiral Ernest J. King, a brilliant and aggressive strategist. Admiral King appointed Admiral Chester W. Nimitz as Commander-in-Chief of the Pacific Fleet in late December 1941.

USS Lexington (CV-2) influenced the course of the Pacific War when her air group, together with the air group of USS Yorktown (CV-5),
carried out a brilliantly planned and executed raid on Japanese invasion beachheads at Lae and Salamaua on 10 March 1942.

Admiral King refused to accept the largely defensive role assigned to the United States Pacific Fleet by President Roosevelt and British Prime Minister Winston Churchill at the Arcadia Conference in late December 1941. King ordered Nimitz to defend vital military areas, halt the Japanese advance, keep the lines of communication with Australia open, and mount offensives against the Japanese with his three aircraft carriers USS Enterprise, Lexington, and Saratoga which had escaped the devastating Japanese attack on the American battleship fleet at Pearl Harbor.

Admiral King ordered the carrier USS Yorktown to cease convoy duty in the Atlantic and rejoin the Pacific Fleet. Yorktown arrived at San Diego on 30 December 1941. The return of Yorktown from the Atlantic was fortunate because Saratoga was hit by a submarine-launched Japanese torpedo south of Hawaii on 11 January 1942 and was unavailable for active service from that date until her return to Pearl Harbor on 6 June 1942.

American carriers raid Japanese military bases in the Pacific

Admiral Nimitz deployed his three aircraft carriers in a series of bold hit-and -run raids against Japanese military forces occupying islands on Japan's vastly expanded defensive perimeters in the Pacific Ocean.

The first American carrier raid was carried out by Enterprise and Yorktown against the Japanese-occupied Marshall and Gilbert Islands on I February 1942. Appalling weather conditions over these islands reduced the effectiveness of the raid, but this demonstration that the US Pacific Fleet was still in business caused concern in Tokyo.

On 14 February 1942, Vice Admiral William F. Halsey's carrier task force TF-8, centred on Enterprise, left Pearl Harbor to carry out hit-and-run raids on America's Wake Island, now occupied by Japanese invaders, and Japan's own Minami-tori Island (also known as Marcus Island), a coral atoll in the central Pacific only 1,000 miles (1,600 kilometres) south-east of Tokyo. The raid on Minami-tori Island produced alarm at the headquarters of the Japanese Navy's Combined Fleet because it was so close to Japan's four home islands.

The Japanese capture Rabaul

The port of Rabaul is situated on the island of New Britain which lies off the north-eastern coast of the New Guinea mainland. As early as August 1941, the Japanese had been planning to capture the town of Rabaul with its fine harbour. The inclusion of Rabaul in the First Operational Phase following the Japanese attack on Pearl Harbor was instigated by Vice Admiral Shigeyoshi Inoue, commander of Japan's 4th Fleet or South Seas Force. Rabaul was only 700 miles (1,125 km) to the south of Japan's major naval base at Truk in the Caroline Islands, and Inoue believed that the capture of Rabaul was essential to prevent Australia allowing its use by American B-17 heavy bombers to attack Truk. The Japanese also intended to turn Rabaul into their main base for further military operations in New Guinea and the Solomon Islands. On 23 January 1942, five thousand troops of Japan's elite South Seas Detachment stormed ashore at Rabaul. With control of the air and support from the guns of their own warships, the Japanese troops quickly overwhelmed the small and poorly equipped Australian garrison.

In response to the Japanese capture of Rabaul, Admiral Nimitz ordered Vice Admiral Wilson Brown to take Lexington and attack Japanese shipping and shore installations at Rabaul. A Japanese patrol plane detected the approach of the Lexington task force to Rabaul on 20 February 1942, and a formation of eighteen Mitsubishi G4M medium bombers (Allied code-name "Betty") was launched from Rabaul to attack the American carrier. Lexington's F4F Wildcat fighters of squadron VF-3 shot down sixteen of the Japanese bombers. Lexington was not damaged in the attack, but Admiral Brown felt it wise to withdraw now that the Japanese had been alerted to the presence of his carrier group.

The Japanese capture Lae and Salamaua

Having captured Rabaul, the Japanese soon found their new base being subjected to Allied air attacks launched from Lae and Salamaua on the north-eastern coast of the New Guinea mainland and from Port Moresby on the southern coast of the New Guinea mainland. Vice Admiral Inoue was able to persuade Japan's Naval General Staff that Rabaul had to be protected from Allied air raids by Japan occupying Lae, Salamaua, Port Moresby, and the island of Tulagi in the British Solomons. On 29 January 1942, the Commander-in-Chief of Japan's Combined Fleet, Admiral Isoroku Yamamoto, was ordered by Naval General Staff to capture Lae and Salamaua and, having done that, to capture Port Moresby and Tulagi.

The capture of Lae and Salamaua would not only eliminate two sources of Allied air raids on Rabaul but also provide the Japanese with forward airstrips from which their attack on Port Moresby could be supported. The capture of Port Moresby was an important aspect of the Japanese plan to sever communications between the United States and Australia. Port Moresby would provide the Japanese with a base from which they could launch bombing strikes deep into the Australian mainland and across the Coral Sea. It would enable the Japanese to block sea access to Australia's northern port of Darwin from the east. The Port Moresby operation was given the code reference "MO" and was fixed for April 1942.

Vice Admiral Brown's aborted carrier raid on Rabaul on 20 February caused the Japanese to postpone the capture of Lae and Salamaua until 8 March 1942. The postponement was deemed necessary to replace the large number of Japanese bombers destroyed by Lexington's fighters.

In the pre-dawn darkness of 8 March 1942, and screened by heavy monsoonal rain, Japanese troops began wading ashore from landing barges at the town of Lae and the nearby village of Salamaua. The landings by three thousand Japanese troops were not opposed by the small Australian garrisons which had already begun to withdraw to the small goldmining towns of Bulolo and Wau in the New Guinea highlands where strategically important airstrips were located.

American carriers strike the Japanese beachheads at Lae and Salamaua

While the Japanese were establishing their beachheads at Lae and Salamaua, Lexington and Yorktown were steaming across the Coral Sea with the intention of striking Rabaul. When he became aware from signal intercepts that Japanese landings were under way at Lae and Salamaua, Vice Admiral Brown quickly changed the objective of his raid. He knew that the Japanese would be highly vulnerable to attack while they were engaged in unloading troops and supplies from their invasion transports, so he diverted Lexington and Yorktown to the southern coast of New Guinea, and launched his air strike against the Japanese beachheads from the Gulf of Papua. Before dawn on the morning of 10 March 1942, one hundred and four aircraft from the two American carriers crossed the towering Owen Stanley Range and took the Japanese completely by surprise. For the loss of one American plane, this brilliantly planned and executed raid cost the Japanese four transports sunk, three warships severely damaged, and four other ships damaged. The Japanese commander's own flagship, the cruiser Yubari, received several bomb hits and had to return to Japan for repairs. It was a stunning demonstration to the Japanese that the United States Pacific Fleet was still a force to be reckoned with.

The USS Yorktown (CV-5) is shown on patrol in the Coral Sea. Yorktown participated
with Lexington in the Lae-Salamaua raid that shaped the course of the Pacific War.

The American carrier raids cause the Japanese to review strategic priorities

For the Naval General Staff in Tokyo, the Lae-Salamaua raid reinforced its view that Japan's main strategic priority in the Pacific should be to cut the lines of communication between the United States and Australia. The Lae-Salamaua raid had demonstrated the urgent need for Japan to capture Port Moresby and Tulagi in the British Solomons as quickly as possible. On 15 March 1942, Japan's Imperial General Headquarters agreed with Naval General Staff that cutting the lines of communication between the United States and Australia was to be Japan's strategic priority in the Pacific and would commence with the capture of Port Moresby and Tulagi in April 1942.

The American carrier raids in the first three months of 1942 caused deep concern to Admiral Yamamoto. He was particularly concerned by Vice Admiral Halsey's raid on Minami-tori Island (Marcus Island) because this coral atoll was only 700 miles (1,125km) from Japan, and Yamamoto feared that the American carriers had the capability to raid Tokyo. Japan's military leaders had assured Emperor Hirohito that an American attack on Tokyo could never happen. To ensure the unthinkable did not happen, officers of Japan's Combined Fleet began to plan a complex operation to destroy the American Pacific Fleet at Midway in the central Pacific. The Midway plan would set the stage for disagreement as to Japan's strategic priorities in the Pacific between Naval General Staff and Combined Fleet. It would cause Japan to spread its military resources too thinly across the vast expanse of the Pacific Ocean.

The Lae-Salamaua raid causes revision of Japan's invasion timetables and lays the foundation for the Battle of the Coral Sea

Although not appreciated at the time by Admiral Nimitz, the Lae-Salamaua raid was of vital importance to the Allies for a number of reasons that would become apparent later in 1942. It was a severe blow to Japan's plan to isolate Australia from the United States as quickly as possible because the Japanese had intended to use the sunk and damaged transports as part of the invasion force to capture Port Moresby and Tulagi in April 1942. The Japanese were forced to postpone the capture of Port Moresby and Tulagi for one month to replace the sunk and damaged ships, and because Vice Admiral Inoue insisted that his operations to capture Port Moresby and Tulagi had to be supported by Japanese fleet aircraft carriers. Those carriers could not be made available for operations in the Coral Sea before May 1942. In this way, the Lae-Salamaua raid set the stage for the Battle of the Coral Sea in May 1942. The Battle of the Coral Sea laid the foundation for the American victory at the Battle of Midway.

The Lae-Salamaua raid lays the foundation for Allied victories at Guadalcanal and Kokoda

The Lae-Salamaua raid also laid the foundations for major Allied victories later in 1942 at Guadalcanal and Kokoda.

The capture of the island of Tulagi and its employment as a Japanese naval flying boat base was a preliminary to establishment of a Japanese forward airstrip a short distance away at Lunga Point on the northern coast of Guadalcanal. The one month delay in the capture of Tulagi produced by the Lae-Salamaua raid also delayed construction of the Japanese forward airstrip on Guadalcanal by at least one month. This delay provided the Americans with time to prepare a large landing force to capture the Japanese airstrip being built on Guadalcanal. Even so, the Americans barely reached Guadalcanal in time. When American Marines landed at Lunga Point on 7 August 1942, the Japanese were ready to bring into operation this airstrip that later became famous as Henderson Field. If the Americans had not seized this airstrip when they did, the Guadalcanal Campaign could not have proceeded as it did. An operational Japanese airstrip on Guadalcanal would have been a formidable obstacle to an American landing in 1942.

The Guadalcanal Campaign had a direct impact on the equally bloody fighting between the Japanese and Australians on the Kokoda Track. The Japanese outnumbered the Australians by five to one, were better armed and supplied, and had pushed the Australians slowly back across the Owen Stanley Range to the last ridge before Port Moresby. Although suffering terrible losses from Japanese mountain artillery, the Australians dug in to make a final stand. From the heights of the Owen Stanleys, the starving and exhausted men of Major General Horii's South Seas Detachment could actually see the searchlights sweeping the night sky at Port Moresby and the Japanese general begged for reinforcements for his final push to capture the vital Allied base.  Because of heavy Japanese losses at Guadalcanal, Major General Horii was denied reinforcements and he was forced to retreat to his beachheads with the Australians in hot pursuit.  If the Guadalcanal Campaign had not been initiated in August 1942, Horii would almost certainly have been reinforced and Port Moresby would have been lost to the Allies.

It will be apparent from the foregoing that the barely acknowledged Lae-Salamaua raid by Lexington and Yorktown produced consequences for the Pacific War out of all proportion to the damage inflicted on the Japanese by that raid.