"Love" Day

[Vulture6]

Love Day

June 15th, 1944 was “Love” Day – or L-Day. Coming just 8 days after the Normandy invasion, forever known as D-Day, the Navy and Marine planners for the invasion of the Saipan in the Marianas Islands designated their landing day as “L” day so that the American people and press would not confuse their operation – the largest amphibious assault to date in the Pacific – with the landings on the continent of Europe.

Vice Admiral Mitscher’s Task Force 58 opened the attack on the Marianas by shelling Japanese positions on Saipan, Tinian, Rota, Pagan, and Guam at 1300 on 11 June 1944. The invasion force, the Fifth Amphibious Corps consisting of Marine and Army Divisions, was carried by the amphibious task force under Vice Admiral Richmond Kelly Turner. The Japanese high command had long suspected that the American’s next step in their Central Pacific drive would pass through the Marianas. They had long expected that Nimitz’s forces would continue their thrust from the Gilbert and Marshall Islands through the Marianas, the Palaus, and the Carolines while MacArthur would continue his thrust across the northern coast of New Guinea toward the Philippines. However, the American actions over the next 96 hours would achieve a level of operational surprise that would ultimately doom the Japanese Empire and change the way that the war would be fought in the Pacific.

Lieutenant General Holland M. “Howlin Mad” Smith, commander of the Fifth Amphibious Corps during the Marianas Campaign referred to the battle for Saipan as “the decisive battle of the Pacific offensive,” and LtGen Yoshitsugu Saito, commander of the Imperial Japanese Northern Marianas Army Group and the 43rd Division wrote that “the fate of the Empire will be decided in this one action.” After the Japanese surrender in 1945, Vice Admiral Shigeyoshi Miwa would say “Our war was lost with the loss of Saipan.” The battle for Saipan and the Marianas saw many firsts for the war in the Pacific, and the loss of the island chain struck the Japanese government to the core. The decision by the American Joint Chiefs of Staff to advance in the Pacific on two fronts – the central Pacific (King / Nimitz) and through northern New Guinea to the Philippines (MacArthur) put the Japanese high command into a dilemma from which they were never able to recover. By active decision or by providence, the events that led up to and came out of the Marianas campaign changed the way that both sides would fight the remainder of the war.

The Marianas are a chain of 15 islands in the central Pacific some 450 miles long, about 1400 miles south-southeast from Tokyo and about 1500 miles east of Manilla. Guam was the largest island of the chain, and had the best harbor. It was also the southernmost major island in the chain. The Marinas were different from what the Marines had experienced during the operations on the flat coral atolls of the Gilberts and Marshalls. The Marinas were volcanic islands and consisted of a variety of terrain with sharp ridges, steep valleys, and narrow beaches. Guam was the most likely target in the Marianas, with Saipan and Tinian lying about 100 miles away.

Saipan had been a German possession prior to World War I, but the Japanese had seized it in 1914, and it was recognized as a Japanese possession by the Treaty of Versailles. In 1920, the League of Nations recognized all of the Marianas, except Guam, as a Japanese possession. They quickly colonized Saipan and many of the other islands, mainly growing sugarcane. By the June 1944, about 30,000 Japanese civilians were living on the island. The island itself was about fourteen-and-a-half miles long and six-and-a-half miles wide. The island of Tinian was about three-and-a-half miles south of Saipan.

The Marianas were a key component of Japan’s inner defensive perimeter. As a result, on 15 June 1944 the Japanese military strength on Saipan was estimated at over 29,000. Lt.Gen. Hideyoshi Obata was the commanding general of the 31st Army, and was the senior commander for the Marianas. Under him on Saipan was Lt.Gen. Yoshitsugu Saito, commander of the Northern Marianas Army group and commanding general of the 43rd Division (reinforced). He had 22,702 troops at his disposal, including several independent infantry units, artillery, and a tank regiment. Also on the island was the Imperial Japanese Navy’s 5th Base Force and the headquarters for their diminished Central Pacific Fleet. The IJN forces were under the command of Vice Admiral Chuichi Nagumo, who had gained fame as the strike force commander for the attack on Pearl Harbor. He had fallen out of favor after the defeat at Midway and was eventually assigned command of the naval forces in the Marianas. Nagumo’s forces on Saipan totaled about 7000.

After the fall of the Marshall Islands, Tokyo wanted to strengthen their inner defensive perimeter. They planned to transfer troops from China to the Marianas and the Carolines throughout 1944. They planned a total of 14 airfields and two seaplane bases in the Marianas, providing a home to over 600 aircraft. The last troop and resupply convoy to reach Saipan arrived in early June 1944. The convoy of seven ships was carrying supplies, fuel, and 10,000 troops and their equipment. As the convoy neared Saipan, it was attacked by two U.S. submarines. Five of the seven ships were sunk. Over 8,000 troops made it to Saipan, but most of their supplies and equipment were lost.

The U.S. forces for the Marianas consisted of the largest amphibious force assembled to date for operations in the Pacific, consisting of some 535 ships and over 127,000 troops. The Northern Troops and Landing Force (NTLF) was commanded by Marine LtGen Holland M. “Howlin’ Mad” Smith. His ground combat forces consisted of the 2nd Marine Division, the 4th Marine Division, and the 27th Infantry Division (U.S. Army). The Southern Troops and Landing Force (STLF) was commanded by Marine Major General Roy S. Geiger and were assigned for the Guam invasion.

For Operation FORAGER, the code named assigned to the invasion of the Marianas, LtGen Smith was teamed again with VAdm Richmond Kelly Turner. They decided to bypass Guam and invade Saipan first. Saipan was the northernmost island in the Marianas with a harbor and a suitable airfield. By taking Saipan first, they would prevent the Japanese from having an advanced staging base from which they would be able to interfere with the invasion of Guam. While Japan anticipated an invasion of the Marianas, they did not plan to have their defensive preparations on Saipan complete until November 1944. When the Americans landed, many of the coastal defense guns were not yet mounted, and many and many positions not finished.

Vice Admiral Mitscher’s strikes on 11 June effectively caught the Japanese in the Marianas flat footed. The 225 plane strike from Task Force 58’s 16 fast carriers destroyed over 30% of the Japanese aircraft in the Marianas, mostly on the ground. While the carrier air strikes continued over the next several days, it wasn’t until Admiral Jesse B. Olendorf’s 7 battleships delivered over 2400 sixteen inch shells in the pre-landing bombardment on the June 13-14 that Tokyo realized that Saipan was the primary target. “The attack on Saipan’s western beaches in the early morning hours of June 15 achieved a strategic surprise, to a greater degree, perhaps, than the American planners had dared to hope.” To measure the amount of surprise, one need only look at the taskings of the IJN Mobile Fleet. Admiral Toyoda had initially dispatched a relief force for Biak Island of northern New Guinea on 3 June and again on 7 June. Less than one week later, he was countermanding those orders to re-direct the Mobile Fleet to the rescue of Saipan.

At 0400 on 15 June, the day of the invasion, over 300 Navy frogmen conducted reconnaissance of the reefs off the landing beaches on Saipan’s western coast. They found that the reefs had not been mined and no obstacles had been built, though there were flags and buoys marking artillery and mortar registration. After the UDTs had been recovered, the surface bombardment started again at 0545, halting only for air strikes at 0700. During their defensive preparations, LtGen Obata had felt that the most likely landing beaches were on the eastern side of the island, since there was no protective coral reef, like there was on the western coast. In the landing zone, this reef ranged from 250 to 750 yards wide and was covered by about four feet of water on the morning of the landing. Because of the shallowness of the reef, the Navy guide boats were tasked with getting the Marine’s amphtracs only to the right part of the reef, leaving it to the amphtrac drivers to cross the reef and the 600 yard wide lagoon to get to the right part of the landing beach. Nonetheless, over 600 landing craft crossed the line of departure shortly after 0800 carrying 8000 troops toward the landing beaches stretching 10,000 yards centered on the village of Charan Kanoa. At the same time, another large force of landing craft circled 5000 yards off the town of Garapan. As the first waves landed, this force turned back to the south and returned to their ships. This deception effectively held the Japanese 135th regiment in place, while the main landing force came ashore several thousand yards to the south.

The Marines landed across the narrow western beaches of Saipan at 0843, and within 20 minutes over 8000 Marines from the 2nd and 4th Marine Divisions were pushing inland under intense indirect and direct fires. The landing beaches were narrow, and the Marines quickly moved off the beaches and inland. In the 2nd Marine Division (2nd MarDiv) zone, the 6th Marines were able to push inland about a mile by the end of the day, but the 8th Marines were pinned down from enfilading fire from dug in Japanese on Afetna Point. Further to the south in the 4th Marine Division (4th MarDiv), the 25th Marines met stiff resistance, with one battalion gaining only 12 yards in the first two hours. But by the end of the day, the 4th MarDiv had reached its day one objectives, and over 20,000 troops, plus artillery, had been landed. While the Marines were established ashore, they had paid a heavy price to do so, with some units in the first wave suffering over 35% casualties, the tally for the first day was over 2500, or more than 10% of the forces ashore. And the Japanese still held the hills and ridges overlooking the Marines’ positions.

The Japanese had decided to defend Saipan at the coast through a series of strong points. They held to the defensive strategy of trying to stop the invasion at the beach, as they had tried to do in the Gilberts and the Marshalls. On Saipan they had concentrated their defense on the eastern shores, but quickly readjusted to face the Marine landings on the western beaches. As the sun set on 15 June, the Marines were digging in and consolidating their positions, and were preparing for the expected night attack and banzai charges. Shortly after dark, the Japanese began probing attacks, looking for gaps and weak spots in the American lines. Then, at 0300 on 16 June, a battalion of the 136th Japanese Infantry Regiment, supported by tanks attacked in dispersed formations across the front of the 6th Marines. Destroyers off the coast quickly illuminated the battlefield by firing star shells, and the USS California brought its five inch guns to bear. By morning, over 700 Japanese bodies were left in front of the 6th Marines position. (USMC 278) In the 4th MarDiv zone, other night attacks came but were supported by artillery. The results, however, were similar.

On the morning of the 16th, the Marines held the positions that they had gained on D-Day. They worked to consolidate their line, mop up any Japanese that had been bypassed, and called supporting arms and air strikes on the hills before them. Starting around noon, the attack kicked off again, but gains were minimal. General Saito had determined that his forces would hold out on the high ground of the 1554 foot tall Mount Tapotchau until the relief force recently turned back from Biak arrived. His troops were dug in to caves and cliff faces in the rugged terrain and he believed that they could hold. Meanwhile, he petitioned Tokyo for air support and continued to use his artillery to shell the beachhead. There had been no Japanese air support at Kwajalein or Eniwetok, but Tokyo managed to launch at least 70 air strikes against the ships around Saipan and the Marines ashore.

Admiral Ozawa’s Mobile Fleet had been spotted by U.S. submarines and its progress closely reported to Admiral Spruance. In order to protect his transports, he ordered all of them to sail east of Saipan on the evening of 17 June. Because the resistance ashore had been tougher than anticipated, LtGen Smith ordered as much of his reserves landed as was possible before the transports left. This brought all of the Marine forces ashore as well as the two regiments (136th Infantry and the 105th Infantry) of the U.S. Army’s 27th Infantry Division (27th ID). Smith specifically ordered that the 27th ID should land its artillery first. Artillery was proving to be essential because naval gunfire was not able to achieve the high angle trajectory necessary to strike the Japanese positions dug in on the reverse slopes of the ridges in central Saipan. It was also essential for counter-battery fires, as the Marines were facing concentrated and effective Japanese artillery fire for the first time since Bataan and Corregidor.

The defeat of Ozawa’s force at the Battle of the Philippine Sea and the destruction of a large portion of Japan’s remaining carrier aviation at the “Great Marianas Turkey Shoot” ended any hope of reinforcement for the Saipan garrison. So General Saito determined to extract as high a price as possible for his island. He still had artillery, tanks, and well over half of his troops, but his forces were short on supplies, ammunition, and especially water.

The Americans, however, were not facing similar logistical problems. Even though the amphibious task force had stopped unloading and the transports had left the area, a mountain of supplies had already been unloaded. Improvements in beachmaster units and the increased use of DUKWs allowed for the rapid build up of necessary supplies over a short period of time. The situation on Saipan when the transports left was very different from the situation on Guadalcanal when the Navy departed.

On the night of 16 June, General Saito launched a massive counterattack again in the 2nd MarDiv zone of action, centered primarily on the 1st Battalion, 6th Marines (1/6). The attack would be headed by the 9th Tank Regiment and supported by the 136th Infantry Regiment and the 1st Yokosuka Special Naval Landing Force. They were to attack through the 2nd MarDiv lines and focus first on retaking the Saipan radio station, some 400 yards to the rear of the Marines’ lines. This attack was to be personally led by Vice Admiral Chuichi Nagumo, the hero of Pearl Harbor and the disgraced scapegoat of the defeat at the Battle of Midway. Aerial observers had spotted the Japanese armor massing just before dark, so the Marines were prepared. The attack commenced around 0330 on the 17th and by the time it ended around 0620, one artillery battalion fired over 940 75mm rounds to break up the attack. With the counterattack over, there were at least 24 newly destroyed tanks in front of 1/6’s position, mixed in with the tanks destroyed the night before. There were also an additional 300 bodies. 1/6 had suffered 78 casualties, and 2nd Battalion, 2nd Marines (2/2) adjacent to the battle, lost 19 men. This was the last major offensive action that Saito would take until almost three weeks later when all hope was lost.

Later that afternoon, the 165th Infantry Regiment (27th ID) took up position on the right of the Marine’s line and the 105th Infantry joined them the next morning. On 18 June, the 4th MarDiv managed to push across the island to Magicienne Bay, cutting off the Japanese forces on the southern third of the island. The same day the 165th Infantry and the 105th Infantry pushed south and captured Aslito Airfield. By 20 June, the 4th MarDiv turned north and tied in with the 2nd MarDiv so that the two divisions had a continuous front facing Saito’s next defensive line. The two Army regiments continued to push south against light resistance and established a line across the Nafutan Peninsula, where the Japanese were dug in on numerous rocky slopes, draws, and ravines. The 20th also saw the return of the transports and the remainder of the 27th ID came ashore.

After resupplying and mopping up Japanese positions that had been bypassed, the Americans resumed the offensive on the 22nd. The 105th Infantry made minimal progress against the forces on the Nafutan Peninsula while the two Marine divisions pushed forward several hundred yards until they hit Saito’s new defensive line. The 27th ID was in Corps reserve, and the first P-47s of the 19th Fighter Squadron flew their first missions from Aslito Airfield. The next several days saw costly progress on all fronts.

The 27th ID, minus the 105th Infantry, was put into the center of the line between the 2nd and 4th MarDivs, but had a variety of problems. Attacks were not coordinated with the regiments stepping off at different times. Units easily became intermixed, and any gains made during the day were given up at night. While these soldiers were facing a determined enemy in extremely difficult terrain, LtGen H.M. Smith expressed disappointment in their lack of progress and their lack of aggressiveness. The 27th ID commander, Major General Ralph C. Smith acknowledged that he too was disappointed with the way his regiments were fighting and promised to personally make sure that the next day’s attacks were more productive. Unfortunately, MGen Smith was willing to give his regimental commanders one more chance that LtGen Smith was willing to give him. As the three divisions resumed the attack on the 24th, the 2nd and 4th MarDivs had to halt their advance and employ their reserves to cover their flanks that were exposed when the 27th ID attack stalled as soon as it started, leaving the U.S. line in a giant horseshoe, with the 27th ID a mile behind the Marine divisions on both flanks. After discussing the issue with MGen Sanderford Jarman (the Army commander of the garrison force for Saipan), Admiral Turner, and Admiral Spruance, LtGen Smith relieved MGen Ralph Smith of his command of the 27th ID. He placed Jarman in command until a replacement could be brought in from Hawaii. This was a decision that would fuel controversy throughout the rest of the war and into the 1950s.

The next day, the 27th ID managed to push forward, bypassing the worst of the positions in places that had earned the names Death Valley, Purple Heart Ridge, and Hell’s Pocket. Their progress allowed the 2nd MarDiv to seize Mount Tapotchau, clearing out the artillery observers that had been calling accurate fire down on the American positions. Also on the 25th, the 4th MarDiv was able to clear and secure the Kagman Peninsula. By this time, though, the Japanese situation was becoming desperate. Many Japanese troops were dependent on rain for drinking water.

The situation was bad enough on the Nafutan Peninsula that every able bodied soldier attempted to infiltrate through the lines of the 105th Infantry. Those who were wounded and not able to make the movement were to engage the enemy from their positions and then commit suicide before being captured. The 500 soldiers who were able to make the infiltration broke out onto Aslito Airfield and several artillery batteries. They were annihilated by 2nd Battalion, 2nd Marines who were in Division reserve.

The three divisions continued to pound forward against the Japanese lines. New tactics were developed to either drive the Japanese from their caves or seal them in. Infantrymen with flamethrowers or engineers with satchel charges worked in teams of 4 or 6 to creep up on the caves. Many caves were mutually supporting, and some had large steel doors to protect the occupants. By 2 July the Americans had broken through Saito’s final line and were falling back to the ridges and hills around Marpi Point on the north end of the island. By 4 July the city of Garapan fell to the 2nd MarDiv and the 27th ID and the 4th MarDiv pressed on, pushing the Japanese north.

Before dawn on 7 July, General Saito launched his last attack. He radioed his apologies to the Emperor and ordered over 4000 soldiers to conduct what was the largest Banzai charge up to that point of the war. He then took his own life by committing ritual seppuku. Once the attack was launched, Admiral Nagumo shot himself with his own pistol. The Banzai charge started just before dawn and quickly overran the line of the 105th Infantry regiment and hit the artillery positions of the 10th Marines. Elements of he 2nd MarDiv then in Corps reserve was able to defeat the attack by about noon. Though it was virtually the end of coordinated action by the Japanese, it cost the U.S. over 1000 casualties.

Within two days, the 4th MarDiv had advanced all the way to Marpi Point. There they witnessed some 800 Japanese soldiers and civilians throw themselves off the cliffs. Other soldiers swam from the beach out to the reef to await high tide. They had been taught to fear capture by the Americans as something worse than death. When news of the fall of Saipan reached Tokyo, Prime Minister Tojo and his government resigned.

The Battle for Saipan was important for many reasons. It saw huge improvements in the organization and functioning of shore parties. The assault troops were transferred to their LSTs only days before the landing, allowing them to embark their LVTs aboard ship rather than climbing down cargo nets. LSTs were also brought inshore on the evening of D-Day to act as floating hospitals. Tactical deception was planned and employed with great effect during the landing, and would be repeated at Tinian and several other landings throughout the rest of the war. Flame tanks and flamethrowers were employed in close cooperation with the infantry to defeat dug in enemy. Close air support techniques were refined, and Navajo Indians were employed as “code talkers” for the first time to coordinate naval gunfire and artillery fires.

The battle also went a long way toward extending inter-service rivalries. The Army convened a board of inquiry around the circumstances resulting in the relief of MGen Ralph Smith. The board found that while LtGen H.M. Smith had the authority to relived Ralph Smith, they felt that the circumstances didn’t warrant it. Ralph Smith was transferred to Europe and given command of another Division. Three days after declaring Saipan secure, LtGen H.M. Smith was given a new command, Fleet Marine Force Pacific (FMFPAC), where he would no longer have command over any Army troops.

On a strategic basis, the seizure of Saipan allowed the Army Air Force to strike directly at the Japanese home islands. Nine days after the invasion, on 24 June, the Army Air Force began work on extending Aslito Airfield to accommodate the B29 Superfortress. On 24 November 1944, one hundred B29s took off from Saipan to strike Tokyo, the first since Doolittle’s raid in 1942. The 2nd MarDiv landed on Tinian two weeks after Saipan was secured. In a footnote to history, Imperial Japanese Army Captain Sakeo Oba and 46 soldiers held out on Saipan until December 1945.








Author’s note: For anyone who is interested, I can supply references and notes for this paper. For anyone who wants to claim all or portions of this paper as their own, be advised that I have removed the notations for the 40+ notes and references (I might have missed a few, if you find random numbers that don’t make sense in the body of the paper.) This paper has also been logged through “TurnItIn.com” – so if you try to claim it as your own academic work, you’ll most likely get nailed… but I’ll be happy to provide a list of sources if you want to use this as a baseline to start any research. – V.