During the early part of June Adachi began preparations for an attack on the American lines along the Driniumor River, twenty miles east of Aitape. The width of the river varies from thirty to ninety yards, and except for short periods when heavy rain turns it into a muddy torrent, it is easily crossed by troops on foot, especially using the numerous rocks, downed trees, and sandbars that dot the river. The Driniumor runs down from the Torricelli Mountains through the tiny village of Afua at the foot of the mountains, and then meanders its way roughly seven miles to the sea.
Japanese reconnaissance patrols reported that the river was lightly defended along its west bank, and that there were numerous Allied supply dumps containing large quantities of food in the area. This food was the main attraction for many of the starving Japanese soldiers. For some, it would prove their undoing as they exposed themselves to enemy fire in desperate attempts to get something to eat. Stretched in a thin line along the river were American troops, mostly from the 32nd Infantry Division.
General Adachi did not know that American code breakers had intercepted radio communications between him and Anami that revealed his plan for a major assault at Aitape. They were even able to keep bearings on his transmitter location as he moved his headquarters from Boikin, twenty miles west of Wewak, farther west to be closer to the planned action.3
Then, to Adachi’s surprise, on June 20 Imperial Headquarters transferred the Eighteenth Army from Anami’s command to that of General Hisaichi Terauchi, commander in chief of the Southern Expeditionary Army, which was superior to Anami’s Second Area Army. On June 21, Terauchi sent Adachi orders to limit his forces to “delaying action at strategic positions in Eastern New Guinea.”4
The change in the chain of command for Adachi’s army and the order to engage in delaying actions were in part the result of a May 6 U.S. submarine attack on a convoy sailing from the Philippines to New Guinea. On board the ships were the 32nd and 35th Infantry Divisions, intended to reinforce Anami and his Second Area Army. Anami was to use these two divisions to attack Hollandia and Aitape from the west, while Adachi attacked Aitape from the east, the aim being to pin the Americans at Hollandia and Aitape inside a powerful pincer. The torpedo attack, however, cost the two divisions most of their artillery and infantry weapons. Imperial General Headquarters rejected a request by Anami that the survivors from the two divisions continue with the original plan to join him. Instead, the troops were sent elsewhere and, to add insult to injury, a new defense line was established that left most of New Guinea, except for the Vogelkop Peninsula at its very western end, and the island of Sansapor, on the wrong side of the line, with instructions to hold out against the enemy “as long as possible.”5
The changed orders and the new primary defense line altered the equation for Adachi. His Eighteenth Army was now more than six hundred miles inside enemy territory. It was clear he had been written off by Tokyo and no attempt could or would be made to reinforce, resupply, or evacuate his army. The nearly sixty thousand men—the number was declining daily, and MacArthur’s headquarters put the remaining troops at between forty-five and fifty thousand—were left to die for their emperor.
If Adachi was no longer required to move into Dutch New Guinea in support of the Second Area Army, but to remain in place and engage in delaying actions, he could cancel the dangerous attack on Aitape. However, there was still the matter of providing for his sick and starving men. With no possibility of outside help, the Eighteenth Army was on its own in a struggle to survive. Adachi had no choice but to look on the planned Aitape attack as a “delaying action” and carry on with his plans. The alternative was to continue watching his army wither away as more men died or abandoned their posts and slipped off into the jungle in search of food and an escape route.
At first, General MacArthur believed that it was “improbable” that the abandoned Japanese Eighteenth Army could “seriously menace” his forces at Aitape. His staff estimated it would take the enemy weeks to trek through the jungle to reach the Driniumor, and those that did would not be fit for combat.6
Then MacArthur received a report from General Willoughby concerning a decrypted message from the Japanese Southern Expeditionary Army to Tokyo, asking that a submarine be rushed to Wewak with supplies that were needed by the Eighteenth Army for its planned attack on Aitape. Coupled with air-reconnaissance photos, PT boat patrol reports, and information provided by the local native population, it was clear that General Adachi was indeed planning a major assault on Aitape.7
Adachi’s plan was to engage slightly over half his force in a concentrated attack at Aitape, leaving a smaller number behind to defend Wewak. He told his soldiers, “I am determined to destroy the enemy in Aitape by attacking him ruthlessly with the concentration of our entire force in that area. This will be our final opportunity to employ our entire strength to annihilate the enemy.” It was an act of desperation, but he could not “find any means or method which will solve this situation strategically or tactically.”8
In late May, more than twenty thousand Japanese began making their way along narrow jungle trails toward the Driniumor River. Their lines stretched for miles as they trudged through swamps and mud while under the occasional driving rainstorm. Despite their physical condition, they remained a determined and powerful force. The two main units for the attack were the 20th Division and the 41st Division. Added to their number was one regiment of the 51st Division. The total number of troops is deceptive, however, since few of these were actually infantry troops with combat training. Surviving records indicate that the force Adachi sent to Aitape contained fewer than eight thousand trained infantry soldiers. Another 2,500 were members of various field artillery units who somehow managed to drag along their 70mm and 75mm guns. Roughly five thousand more were to engage in support and supply roles for the infantry and artillery soldiers and fight when called on. The remaining 4,500 were a mix of maintenance men, headquarters clerks, and soldiers in other noncombat jobs who were to fight when it was required. Adachi left twenty thousand men to defend Wewak against harassing attacks by the Australian 5th Division, which had fought its way to within sixty miles of Wewak. Another fifteen thousand Japanese troops were to follow behind the attacking force with whatever supplies could be gathered in the Wewak area.9
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During the weeks of marching, the Eighteenth Army remained in regular radio contact with the Southern Expeditionary Army headquarters, allowing American radio interceptors to keep track of its progress. General Willoughby reported that at the beginning of the march the Japanese were making about six to seven miles per day, whereas weeks later they were making less than half that number.10
Reconnaissance patrols Adachi had sent far ahead of the main troops reported that he could expect only two regiments of Americans defending the west bank of the Driniumor River. This was correct, but then, in anticipation of the impending attack, General MacArthur ordered the 43rd Division under Major General Leonard F. Wing to Aitape. This New England National Guard division was rushing from New Zealand. Concerned it would not arrive in time, General Krueger sent in the 112th Cavalry Regiment and the 124th Infantry Regiment from the 31st Division in support of the 32nd Division, which was the main line of defense on the scene. With two divisions and elements of a third at Aitape, the defending force came under the command of Major General Charles Hall’s XI Corps.11
In late June, American patrols began reporting the presence of Japanese soldiers on the opposite side of the river. At first they appeared to be reconnaissance patrols, but then they were revealed as combat units. Firefights ensued.
On July 17, the regiments of the U.S. 43rd Division started arriving from New Zealand to support the Aitape defense line. One of its four regiments was the 169th, from Connecticut. Tokyo Rose announced the arrival of the 169th in New Guinea, calling the regiment the “Butchers of Munda,” a reference to the ferocious fighting it had engaged in to capture Munda, on New Georgia
, in July and August 1943.12
As small-unit engagements increased and grew in intensity around the Driniumor River, MacArthur pressed Krueger to end the fighting and send the enemy troops fleeing. Krueger ordered two large-scale reconnaissance forces across the river to ascertain exactly where the enemy was and the size of their force. On July 10 a battalion from the 128th RCT and a squadron from the 112th Cavalry crossed to the east side of the river at separate locations and began a surprisingly fruitless search for the enemy’s main force. The thick jungle limited visibility, and despite the fact that there were thousands of Japanese troops nearby, the Americans never caught sight of them. Unfortunately, these men were so far east they would not be available to defend the river line when Adachi launched his main attack at eleven thirty that night.
The attack began with a ten-minute artillery barrage, which surprised the Americans, who were unaware the enemy had dragged some of their heavy weapons through the jungle. Near the mouth of the river, a battalion from the Japanese 78th Regiment began crossing the river, expecting only light resistance. Well-prepared American artillery and mortars decimated them. Of the four hundred emperor’s soldiers who entered the river, barely ninety survived. Farther upriver, another battalion suffered a similar fate, although some men were able to get to the opposite shore and work their way around back of the defenders.13
At the northern end of the river, Japanese troops from the 237th Infantry regiment and the 20th Division attacked across the river on a seventy-five-yard-wide front. Although they, too, suffered heavy losses, they were able to establish a beachhead on the American side and drive the defenders to a second line of defense at the River X-Ray, some three thousand yards back. Adachi took advantage of this small breakthrough by pouring every available unit through the area abandoned by the Americans. Thinking success was within his reach, the Japanese general decided to commit his reserve units to the fight as quickly as possible. Unfortunately, most of these units were still marching through the jungle and had not reached the front.14
In spite of their losses, the troops of the 78th Regiment continued to pour across the river near its mouth, pushing the Americans back. General Krueger ordered a halt to withdrawal and instructed General Hall to mount a counterattack and regain the Driniumor River line. Both sides kept sending more troops into the many skirmishes and battles up and down the river. The fighting was especially intense around the village of Afua, at the foot of the Torricelli Mountains where the river begins its push toward the sea, with control of the area changing hands several times over the next two weeks.
On July 31, General Hall ordered three battalions from the 124th Regimental Combat Team across the river near its mouth with orders to move south along the east side of the river toward Afua. By then, the Americans had reoccupied all the areas where the Japanese had crossed the river, and numerous Japanese units found themselves isolated behind enemy lines. With American units now on what had been his side of the river, and his losses mounting, Adachi was forced to rethink his plans. His troops were running dangerously low on ammunition, and many were completely out of food rations, forced to live off jungle plants and the small amount of food they recovered from temporarily abandoned American positions. Several regiments reported they were down to fewer than one hundred men, with several as low as thirty soldiers accounted for. Finally, on August 4, Adachi ordered a halt to all attacks and instructed his surviving officers to begin the trek back toward Wewak. Although the actual number of Japanese casualties has never been determined, the fighting along the Driniumor cost the Eighteenth Army between nine thousand and thirteen thousand dead.15
Combat continued for several more weeks as Japanese troops attempted to fight their way from behind American lines and return across the river. The battle for Driniumor River cost fewer than six hundred American lives, and approximately 170 men wounded. Another eighty-five remained missing in the dense jungle. The official U.S. Army history acknowledges that the fighting along the river constituted a “major battle,” but it was incidental to the progress of MacArthur’s drive toward the Philippines.16
Pursued by American long-range patrols, the Japanese Eighteenth Army limped back to where it had come from, losing thousands more men along the way. General Adachi himself later described the story of his Army as “tragic.”17
CHAPTER 21
Island-Hopping to Victory
By the late spring of 1944, the war in New Guinea was beginning to wind down for General Douglas MacArthur and the fifteen U.S. Army divisions he commanded, along with the American air and naval forces he planned to take with him to the Philippines.1
MacArthur’s primary need, as his forces battled the enemy at various locations in New Guinea, was to keep the momentum going and to build additional airfields that could accommodate long-range heavy bombers and fighters, all the while avoiding massed Japanese concentrations. His next target was the area around the Vogelkop, or Bird’s Head Peninsula, at the northwestern end of New Guinea. The name derives from the shape of the peninsula, which resembles the head of a large bird. The 8,500-square-mile jungle- and mountain-filled stretch was home to tens of thousands of Japanese troops. Their two main concentrations were at Sorong, at the front of the bird’s head, facing west, and Manokwari, at the rear of the bird’s head, facing east. The Vogelkop was, in MacArthur’s words, “the last enemy stronghold in New Guinea.” His plan was to bypass both locations and capture, instead, offshore islands that could help isolate the enemy troops and provide additional airfields for General Kenney’s forces.2
First on the list was Noemfoor Island. Located approximately seventy-five miles west of Biak, and sixty-five miles east Manokwari, where twenty-five thousand Japanese troops would soon be bottled up with no means of escape, it was the obvious first step to surrounding the Vogelkop. Almost circular in shape, Noemfoor is eleven miles in diameter at its narrowest. It is roughly fifteen miles north to south and twelve miles east to west. When the first Japanese arrived in December 1943, the local population of approximately five thousand who lived in coastal villages must have sensed the danger they represented, as they fled to the dense forests of the island’s interior.3
Unable to use locals as construction workers, the Japanese imported three thousand Javanese men, women, and children to toil as slave laborers, building the three airfields they planned. Only four hundred of these people would be found alive by the Allies, the rest having died from mistreatment, starvation, disease, and injuries. It was these airfields that made the island so attractive to General Kenney, who first suggested capturing Noemfoor to MacArthur. To the Allies, the most important of these was the completed Kamiri Airfield near the village of the same name and very close to the northwest coast. The strip was five thousand feet long and equipped with dispersal areas for storing aircraft. Built on the coral foundation of the island, it was expected to handle Kenney’s medium bombers. The other airfields were Kornasoren, a few miles east of Kamiri, along the north coast, and Namber, on the southwest coast. The latter two were not yet completed, but well on the way to completion and could quickly be made serviceable for Allied fighters by American and Australian engineers.4
On June 4, 1944, MacArthur ordered his staff to quickly develop plans for the invasion of Noemfoor. One reason for the rush was that he had learned the Japanese were moving troops in small craft, such as luggers, from Manokwari to Noemfoor during the night hours to avoid Allied ships and planes. Once on Noemfoor, they stayed close to shore for the entire day, hidden from reconnaissance aircraft and PT boats. During the following night, they made the seventy-five-mile run to Biak, bringing in reinforcements and supplies. Allied intelligence agents believed this was how the entire Japanese 221st Infantry Regiment arrived at Biak to battle the American invaders.5
Among the first questions the planners had to answer was, “How many Japanese were there to defend Noemfoor?” This was also one of General Krueger’s first questions when MacArthur confirmed
on June 17 that he was to invade, occupy, and defend the island against potential counterattacks, as well as ensure that all three airfields were able to receive Allied bombers and fighters as quickly as possible. Krueger was also instructed to find some way to build an anchorage to handle small naval ships. At the time, Noemfoor contained nothing resembling an anchorage for ships of any size since the island had never engaged in any sort of commerce.6
From reports he was receiving through ULTRA, General Willoughby estimated there were about 1,750 Japanese soldiers on the island, of whom 700 were actually combat troops. The remainder was from airfield construction and transport units, as well as other noncombatants. The Allies did not consider the Indonesian slave laborers or the nine hundred men from a Formosan auxiliary labor force as possible island defenders since they were not expected to fight on behalf of their cruel masters. While Krueger accepted these numbers, he remained concerned about earlier estimates regarding Biak, which had reported numbers of Japanese defenders far less than what his men had encountered there. He suspected that reinforcements were even then slipping into Noemfoor, given that it should be obvious to the Japanese that the island was the next Allied target. Krueger decided to send in the Alamo Scouts for a definitive answer.7
Adding to Allied worry about the planned amphibious invasion of Noemfoor was a coded Japanese message dated June 19 that revealed the shipment of nine coastal defense guns to the island.8
Air reconnaissance photos revealed the island surrounded by a coral reef, with only a few openings through which small craft could reach the beach. One of these was directly opposite the Kamiri Airfield, a contributing factor to that field’s attractiveness as the initial target of MacArthur’s proposed amphibious landings.
War at the End of the World Page 39
