Carrier USS Lexington under Japanese Attack.
By the time that the IJA had sewn up its occupation of Sumatra and Java in the second week of March 1942, they had possession of those islands among the 17,500 of the Dutch East Indies that mattered. The growing empire of Emperor Hirohito now included the oil fields, and a Japanese governor seated in the jewel of the former Dutch colonial crown. The momentum of the invincible IJA invited – indeed it demanded – a next step.
Looking eastward from the Dutch East Indies lay New Guinea, the second largest of the world’s islands. Bracketed by Japanese-occupied Ambon and Timor to the west and Japanese-occupied New Britain to the east, it spanned 20 degrees of the earth’s longitude. On the chessboard of the intersection between Southeast Asia and the Southwest Pacific, ownership of New Guinea appeared essential to the Japanese strategy of containing Australia and any offensive that the Allies might launch from Australia.
Aside from its place on the map, and an enormous place it is, New Guinea is probably the most improbable slice of real estate to be fought over by the great world powers of the mid-twentieth century. A land of mystery with an unexplored interior, New Guinea is more than twice the size of Japan, but it had fewer census-counted inhabitants than the city of Kobe. It is still a land of impossible terrain where even in the twenty-first century it has yet to be bisected by a highway. It is a place of such remoteness that even many decades after World War II, it was inhabited by multitudes of species not yet catalogued by biologists, and home to numerous groups of stone-age people whose languages had never been heard by anthropologists.
New Guinea had been largely ignored by Europeans until the middle of the nineteenth century, and thereafter they had shown little interest beyond planting their flags. The Dutch had administered the part – or more properly, outposts along the coastline of that part – west of the 141st meridian as Nederlands Nieuw Guinea. The British and the Germans had each claimed a slice of the eastern part until 1919, when this half had been bestowed upon Australia by the League of Nations as the New Guinea Trust Territory. Today, the former Dutch half is part of Indonesia, while the eastern half is the independent state of Papua New Guinea (or Papua Niugini). It is indicative of New Guinea’s “forgotten” status in the affairs of the middle twentieth century that its largest city, Port Moresby on the Australian side, was home to barely 2,000 people in 1941.
It was to this, the eastern half of New Guinea, that the Japanese turned much of their attention after the fall of Java. Specifically, they focused on the 400-mile-long Papuan, or “Bird’s Tail,” Peninsula at the southeast tip of the island. Strategically, this was the part closest to their mushrooming base complex at Rabaul, and on the south side of the Bird’s Tail, Port Moresby was only 300 miles from the Cape York Peninsula in the Australian state of Queensland.
As Port Moresby was the largest city, largest port, and home to a growing concentration of Australian and American forces, it was the ultimate objective of the Japanese New Guinea strategy. In Allied hands, it could threaten Rabaul. In Japanese hands, it could protect Rabaul and be used to threaten Australia.
If most of New Guinea was strategically irrelevant to the Japanese master plan, Port Moresby had been a square on the Southwest Pacific chessboard upon which Japanese planners had been fixating for years. As early as 1938, the IJN had begun drafting plans for its capture as part of anchoring the sea lanes at the southern edge of the Greater East Asia Co-Prosperity Sphere. With the approval of Admiral Isoroku Yamamoto – commander of the Combined Fleet and architect of the Pearl Harbor attack – the plan for the capture of Port Moresby and its use in the chess game against Australia had been designed and filed away for later use. By March 1942, with all of the other pieces in place on the board, it was time to dust off the plans for Operation Mo (or Mo Sakusen, named for the first two Roman letters in “Moresby”).
The opening gambit in Operation Mo and the New Guinea campaign came on March 8, even as surrender terms were being dictated on Java. The initial targets were the twin villages of Lae and Salamaua on the north side of the Bird’s Tail, 200 miles due north of Port Moresby across the Owen Stanley Mountains, from which air support operations could be launched.
Major General Tomitaro Horii, who had led the operations against Guam and Rabaul, had set sail aboard four troop transports from the latter base three days earlier with the IJA’s South Seas Detachment. This organization was under the command structure of the IJN South Seas Force (based on the 4th Fleet), and was based on the 144th Regiment of the 55th Division. Horii’s order of battle for the Lae and Salamaua operation was essentially the same that he had successfully used to capture Rabaul in January. Horii’s troops were escorted by a substantial IJN fleet, including destroyers, patrol boats, and ships from two cruiser divisions. From Rear Admiral Aritomo Goto’s Cruiser Division 6, there were the heavy cruisers Aoba, Furutaka, Kako, and Kinugasa. Contributed by Rear Admiral Marumo Kuninori’s Division 18 were the light cruisers Tatsuta and Tenryu.
The landings on March 8 went like clockwork, just as the IJA had come to expect from their experiences at dozens of beachheads across Southeast Asia since December 8. At Lae, the Japanese troops landed without opposition. At Salamaua, there was sporadic gunfire. Attempts by a handful of Allied aircraft to attack the invaders were swatted away as more of a nuisance than a threat.
Two days later, the situation was surprisingly different, as American aircraft launched a concentrated attack against the ships anchored off the invasion beaches. USN bombers from the carriers USS Lexington and USS Yorktown, as well as eight USAAF B-17 Flying Fortresses operating from Townsville, Australia, did considerable damage. Three of the transports were sunk, and one damaged. Also damaged were a cruiser, two destroyers, and several support vessels. It was not a major defeat, but it was a serious blow to the complacency with which the Japanese had been operating. It was also the harbinger of an ebbing of Japanese air superiority.
As the Japanese began the enormous task of reinforcing Lae and Salamaua in advance of their assault on Port Moresby, parallel operations were getting underway more than a thousand miles to the west. The great battles which unfolded in eastern New Guinea later in 1942 have been discussed in great detail elsewhere, but the Japanese operations in western New Guinea, which flowed from the momentum of the Dutch East Indies Campaign, have been virtually ignored.
The battle plan for the western New Guinea operations was a naval plan. The objectives were the isolated Dutch coastal enclaves across the north side of the island, as well as around the 21,469-square-mile Vogelkop (now Kepela Burung) or “Bird’s Head” Peninsula, which is like an appendage to the northwest corner of New Guinea just as the Papuan Peninsula, the “Bird’s Tail,” is the signature geographic feature on the southeast corner of New Guinea. The plan was simply to use a naval force to pluck the isolated coastal communities one by one.
The spearhead for operations in western New Guinea was the IJN Special Naval Landing Forces. Specifically, they were troops under the command of the 24th Special Base Force, which was part of the IJN 2nd Southern Expeditionary Fleet; this was essentially the IJN 3rd Fleet, renamed on March 10 and given the responsibility for activities within the largely pacified Indies. The invasion force, known as Expeditionary Force N and under the overall command of Rear Admiral Ruitaro Fujita, was organized on Ambon immediately after the conquest of Java, and shipped out on the night of March 29.
Outnumbering the transports, the escort included the light cruiser Kinu, two destroyers, assorted patrol boats, and submarine chasers. Air support was supplied by the seaplane tender Chitose, which had been active in supporting a number of previous landings in the Dutch East Indies. The landing force itself, under IJN Captain S. Shibuya, included a small detachment from the 24th, plus the battalion-sized contingent of infantry from the 4th Guards. It was small relative to those assigned to previous operations because it was correctly assumed that resistance from handfuls of KNIL stragglers would be minimal.
The first objective for Expeditionary Force N was Bula on the eastern tip of the island of Ceram, where there was a small oil production facility. Reaching this on March 31, and finding that it had been abandoned, the Japanese ships steamed westward, making landfall at Fakfak on the western tip of New Guinea proper on April 1. From here, Expeditionary Force N proceeded clockwise around the Vogelkop Peninsula, reaching Sorong on April 4, and Manokwari on April 12. A week later, they reached Hollandia (now Jayapura), near the border with Australian-administered eastern New Guinea, which had been one of the few important Dutch administrative centers on the island.
At each point on this expedition, the Special Naval Landing Forces found their objectives either lightly defended or completely deserted of KNIL troops. Most of the Dutch had long since embarked on a long and difficult escape to Australia, or had escaped into the jungle to conduct guerilla actions against the Japanese. Indeed, in most cases, the defense of western New Guinea had been so insignificant that lightly armed sailors from the warships served as garrison troops. Garrison detachments of IJA forces were not sent to relieve them on a permanent basis for several months. Neither side bothered with the south and southwest coast of western New Guinea, which was inhospitably swampy, and home to few settlements.
Eastern New Guinea, however, was another matter. With the Japanese reinforcing their position at Lae and Salamaua, and the Allies doing the same at Port Moresby, both sides were building toward the pivotal battles that were about to take place on the ground, in the air and on the sea across in eastern New Guinea and across the Southwest Pacific.
Early May was to be a pivotal moment here, as was the middle of January in Borneo or the first week of March on Java. It was the moment when the invincible Japanese war machine would make decisive and simultaneous moves across a vast swathe of ocean and island from Port Moresby, about 870 miles to the east, across the Coral Sea to the islands of Tulagi and Guadalcanal in the Solomon Islands chain.
There was great confidence and no reason to believe that things would not go as they had at every turn for the past five months since the great simultaneous offensives on December 8. If the landings in the Solomons went smoothly, it would advance the Japanese pieces on the chessboard much closer to Australia’s east coast. Japanese air bases here could threaten not only Australia, but its ocean supply lines from the United States.
Tomitaro Horii’s South Seas Detachment, roughly 5,000 strong aboard a dozen transports, departed from Rabaul. The invaders of Tulagi had disembarked from one of the ships, and had gone ashore on Tulagi unopposed on the night of May 3–4, while the rest were bound for their amphibious landing at Port Moresby which was scheduled for May 7.
They were supported by the IJN 4th Fleet under Vice Admiral Shigeyoshi Inoue aboard the cruiser Kashima. It was the largest Japanese naval force assembled in one place since the operations across the Java Sea during the latter half of February. Directly supporting the Port Moresby invasion group was Rear Admiral Sadamichi Kajioka, with the cruiser Yubari, as well as the destroyers Asanagi, Mochizuki, Mutsuki, Oite, Uzuki, and Yayoi. Rear Admiral Aritomo Goto, meanwhile, commanded another covering group that included the light carrier Shoho and the cruisers Aoba, Furutaka, Kako, and Kinugasa. Also on hand was a carrier strike force comprised of the fleet carriers Shokaku and Zuikaku and commanded by Takeo Takagi who had led the virtual obliteration of the Allied fleet in the Java Sea, and who had just been promoted to vice admiral on the first of May.
The meticulous Operation Mo planning had called for the South Seas Detachment to secure Port Moresby by May 10, and Horii was confident that he could deliver. Japanese bombers would be conducting operations against Australia from Port Moresby by the morning of May 11. Before that morning, however, there would be other mornings and the unexpected, which always haunts the overconfident.
On May 4, just as the Japanese had gone ashore on Tulagi, they were attacked by USN aircraft from the USS Lexington and USS Yorktown, part of Rear Admiral Frank Fletcher’s Task Force 17. As the two sides became aware of one another, and Fletcher deduced from intelligence sources that the long-anticipated invasion of Port Moresby was in motion, the opposing fleets searched for one another across the Coral Sea. Two days of maneuvering led to the joining of a remarkable battle on May 7. It was unlike anything that had yet been seen in naval history. The ships of neither side came within striking distance of the other. Throughout May 7 and May 8, the offensive battle was waged entirely by aircraft.
In the battle of the Coral Sea, each side lost a destroyer and several lesser ships damaged or sunk, but most of the attention was focused on the opposing carriers. The Japanese lost the light carrier Shoho, while the Shokaku was put out of action through battle damage, and the Zuikaku’s aircrews were depleted in the fighting. The Lexington was fatally damaged and scuttled, while the Yorktown eventually limped back to Pearl Harbor for repairs. The naval battle was a statistical draw, but a strategic victory for the USN insofar as the Coral Sea marked the high-water mark in a great run of successes for the IJN.
A month later, during the first week of June, Admiral Isoroku Yamamoto prepared for what might have been a brilliant end run victory which, in turn, might have checked the USN in the central Pacific. He sent four fleet carriers to support the invasion of Midway, due north of Hawaii. He had planned to include the Shokakau and Zuikaku, but after the battle of the Coral Sea, they were heading to Japan for repairs and were unavailable. If the battle of the Coral Sea was the end of the beginning for the IJN, the battle of Midway was the beginning of the end. All four of the Japanese carriers, Akagi, Hiryu, Kaga, and Soryu – each a veteran of the Pearl Harbor attack – were sunk at Midway. Things would never again be the same for the IJN.
The battle of the Coral Sea was also the high-water mark for the IJA in the Southwest Pacific. They would hold on in the Solomons, but as the hold began to falter, the momentum was never revived.
What then, of the invasion of Port Moresby, which was scheduled for May 7, and which was to be completed by May 10? As the battle began to unfold in earnest on that day, Admiral Inoue withdrew the invasion fleet. On May 7, with all three aircraft carriers preoccupied and embroiled in the great air battle, they could not support the invasion. Inoue decided that it would not be prudent to go forward with the landings without air cover. By the following day, one of the Japanese carriers was gone and the other two unfit for operations.
Inoue initially ordered a postponement to May 12, then to May 17, and finally the amphibious attack on Port Moresby, which was once just a matter of hours from happening, was cancelled. Inoue was relieved of his command and brought home to desk duty.
General Tomitaro Horii’s South Seas Detachment, meanwhile, were not relieved of their duty. It was decided that instead of coming across the beaches, they would attack overland, across the Owen Stanley Mountains which form the jagged spine of the Bird’s Tail. On July 21, Horii landed on the north shore of the Bird’s Tail in the area of the villages of Buna, Gona, and Sanananda, with around 6,500 men. They then attempted to hike across the mountains on the rough, 65-mile Kokoda Track, a trail which climbs to 3,380 feet through some of the most difficult terrain on earth. Opposing the Japanese were small understrength Australian units – and the land itself.
New Guinea was such a difficult place to wage war that the troops found it a triumph when they managed to march a mile a day through its dense forests. These jungles, with their slippery hillsides tangled in forests and foliage where the sun had never shown, and where visibility is often measured in inches rather than yards, were literally hell on earth for most troops who dared to challenge them.
Being located barely south of the equator gives New Guinea a climate in which a veritable encyclopedia of tropical diseases can flourish. The troops discovered that malaria was almost routine and maladies such as dysentery were actually routine.
The Japanese continued to pour men and materiel into the Kokoda Track for months, eventually losing as many men as they had first committed to the futile campaign. One of them was Horii himself, who drowned crossing a river in September.
The IJA never reached Port Moresby. The momentum lost through the cancellation of the amphibious operation on May 7 was never recaptured. A month later, the battle of Midway guaranteed this. Australia was safe. If there had been an invasion of that country on the books, without Port Moresby, it was impossible.
