$Unique_ID{USH01475} $Pretitle{128} $Title{The Amphibians Came to Conquer: Volume 2 Chapter 21A The Nut Cracker: Saipan - Tinian - Guam} $Subtitle{} $Author{Dyer, VAdm. George C.} $Affiliation{USN} $Subject{pacific japanese marianas saipan admiral amphibious fleet islands general guam} $Volume{Vol. 2} $Date{1973} $Log{} Book: The Amphibians Came to Conquer: Volume 2 Author: Dyer, VAdm. George C. Affiliation: USN Volume: Vol. 2 Date: 1973 Chapter 21A The Nut Cracker: Saipan - Tinian - Guam As was stated earlier, Rear Admiral Turner remained at Kwajalein Atoll until the capture of Eniwetok Atoll had been completed and the garrison forces were readying to take over. He departed in his flagship, Rocky Mount, for Pearl Harbor on 25 February 1944, entering that port on 3 March 1944. During the long, long month commencing on 5 February, he had been sitting on the anxious seat waiting for his promotion to Vice Admiral to be approved by the United States Senate, and more than a bit disturbed by the backstairs gossip surrounding the delay. The hard-fought assaults on Kwajalein and Roi-Namur, and then on Engebi, Eniwetok and Parry, combined with this backlash had worn him down to a nubbin. In an off-hand remark to me he said: When I came back from the Marshalls, I was dead tired. I stayed dead tired for the rest of the war. When this remark was mentioned to Fleet Admiral Nimitz, he leaned back in his chair, his weathered face wreathed in a soft smile, and he spoke softly: Kelly was operating under a forced draft. There were times during this period when I wanted to reach out and shake Kelly. But Spruance always said: 'Let me handle him' and handle him he did. I always attended rehearsals that were held in the Hawaiian Islands. Kelly had a firm hold on rehearsals and did a magnificent job. His insistence on rehearsals was a major factor in his success. And then after a pause, Fleet Admiral Nimitz, the Grand Old Man of the Pacific War, added: I became very much attached to him. It must be added in all honesty that from this period in the war on, an ever increasing number of old shipmates were aware that Kelly Turner was partaking more freely of the liquid that cheers, but all reports indicated that he was handling it extremely well. The Overall Problem of Defeating Japan As Admiral Turner said in 1949 in a speech before the General Line School: To defeat the Japanese, we had long recognized that we must plan ultimately either to invade the home islands or else destroy their armies in Manchuria and North China, and then isolate the home islands by blockade. We also needed to weaken their industry by strategic air bombing in order to reduce their logistics potential at home. Thus it was necessary for us to concentrate large military forces, land, sea, and air, plus heavy stocks of material in bases reasonably close to Japan. In turn, that meant that we required large land deployment areas and large harbors in the Western Pacific Ocean . . . . The only possible suitably adequate areas were the Philippines, Formosa and China, and of these the Philippines was much the best . . . . Planning for the Pacific War Out of the Sextant American-British Conference ending at Cairo, Egypt, on 6 December 1943, came the necessary approved plan to conduct the war against Japan throughout 1944. The Combined Chiefs of Staff and our own Chiefs of Staff never lacked for suggestions or recommendations from the Pacific or the Southwest Pacific commands as to how the war against Japan might be won. And frequently they received contrary recommendations from Admiral Nimitz and General MacArthur. In December 1943, the scales were tipped very lightly in favor of doing what Admiral Nimitz recommended. The Combined Chiefs of Staff, acting in accordance with the recommendations of our Joint Chiefs, did not decide against General MacArthur's plan of advance along the New Guinea-Netherland Indies-Philippine axis. In fact, they decided that one advance would be made along this north-south line toward Japan and another advance would be made along an east-west line passing through the Marianas. The two lines of advance they hoped would be mutually supporting during the early phases. The Joint Chiefs of Staff decided that when conflicts over resources occurred, the Central Pacific Campaign would have priority over the Southwest Pacific Campaign, primarily because it held greater promise of a more rapid advance toward Japan and her essential lines of communication with the south to bring natural resources into the homeland. Based on these high level decisions, Admiral Nimitz promulgated his Granite Plan. This covered the prospective operations against the Japanese in the Central Pacific Ocean Area during 1944. As desired by the Joint Chiefs of Staff, the Marshall Islands would be assaulted early in 1944, with Eniwetok being taken about 1 May 1944. About 15 August, the Mortlock Islands (160 miles southeast of Truk) and Truk Atoll in the Carolines would be taken. Then, about 15 November 1944, Saipan, Tinian, and Guam would be assaulted simultaneously, if possible. All during this period, Admiral King held to the firm opinion that the Marianas were the key to the Western Pacific since, from the Marianas, we could quite easily cut the Japanese line of communications to the Netherland East Indies and Malaysia and from there could bomb Japan. Admiral King also believed that reaching the mainland of China was a major objective of the drive through the center of the Pacific Ocean. This was in order to take advantage strategically, not only of China's geographical position but of her huge manpower. Two things happened in the first seven weeks of 1944 to change the strategic picture further in our favor. 1. The Japanese Combined Fleet retreated from Truk Atoll to the Palau Islands in the Western Carolines. 2. Eniwetok was taken in late February, rather than in early May. Admiral Nimitz, soon after Eniwetok was firmly in hand, wrote to the Commander in Chief, United States Fleet: The capture and consolidation of Kwajalein, Majuro, and Eniwetok, together with the successful Fleet operations against Truk and the Marianas, have created changes in the strategic situation which permits advancing the timing of operations contemplated by the Granite Plan. In a long reasoned discussion, Admiral Nimitz then developed two proposed schedules of future operations, one in which Truk would be assaulted 15 June 1944, with the Southern Marianas assault to follow on 1 September 1944. The other schedule called for Truk to be neutralized and bypassed, and the Southern Marianas to be assaulted on 15 June 1944. Subsequently, Woleai, Yap and the Palaus (about 1060 miles southeast of Manila) were to be captured by 1 November 1944 (later changed to 1 October) Admiral Nimitz believed that following the latter schedule, which advanced the assault date on the Marianas by two and a half months, would permit readiness of his forces in the Pacific Ocean Areas to launch a major assault in the Formosa-Luzon-China area in the spring of 1945. While awaiting the decision by Admiral King and the Joint Chiefs of Staff, Admiral Nimitz's Staff would not be idle. The Admiral wrote Admiral King that: "Plans are being drawn up and forces prepared for either objective [Truk or the Southern Marianas]." It should be recorded here that there was some naval opposition and considerable lack of enthusiasm for the operation to take the Southern Marianas. This arose because of the complete inadequacy of the harbors in Saipan and Tinian and the limited capacity of Apra Harbor, Guam. For a satisfactory mobile logistic support base in this general area it would be necessary for the Pacific Fleet to go 400 miles southwest of Guam to Ulithi Atoll in the Western Caroline Islands. Eniwetok had a fine anchorage, but the rim islands were all too small for the development of shore-based storage and work shop activities. Moreover, it was located a thousand miles back towards Pearl Harbor from the Marianas. Admiral Nimitz's letters to COMINCH and later visits to Washington were occurring against a background of strong urging by General MacArthur during January and February 1944, to do something quite different with the naval forces of the Central Pacific. In early February 1944, General MacArthur was pressing for the commitment of large combatant Pacific Fleet forces on a long continuing basis to support his advance toward the Philippines. In a despatch he said: I propose that with the completion of the operations in the Marshalls, the maximum force from all sources in the Pacific be concentrated in my drive up the New Guinea coast to Mindanao, to be coordinated with a Central Pacific Operation against the Palaus and the support by combatant elements of the Pacific Fleet with orders to contain or destroy the Japanese Fleet. Despite the firm decision of the Combined Chiefs and the Joint Chiefs of December 1943, that the Central Pacific campaign would have priority, General MacArthur sought to advance his own proposals by sending his Chief of Staff and supporting officers to Pearl Harbor, and then on to Washington. Admiral King thought that the proposal to divert major naval resources from the Central Pacific to the Southwest Pacific on a long time basis was "absurd" and so said to anyone within hearing and in a letter to Admiral Nimitz. On 2 March 1944, the Joint Chiefs avoided meeting the issue head on, but did go so far as to state: Our first major objective in the war against Japan will be the vital Luzon-Formosa-China coast area. This tied in with the Central Pacific Campaign far more realistically than the south-north drive up through New Guinea, particularly when coupled with a Joint Chiefs' cancellation of General MacArthur's proposed assault on Kavieng in New Ireland, and advice to him that the Central Pacific Campaign had priority in military resources over the Southwest Pacific Campaign. It was another ten days before the seal of approval to the Central Pacific Campaign and the Granite Plan was reaffirmed. The final Joint Chiefs' decision was to confirm Admiral Nimitz's proposal to assault the Marianas on 15 June 1944. Success in the Marianas, of itself, would largely neutralize Truk and isolate the Central Carolines because it would throttle the main Japanese aircraft pipeline down from the Empire to the Carolines. The Palaus in the far western Carolines would be assaulted on 15 September 1944, with the object of establishing a fleet base there, as well as a forward staging area for later operations against Mindanao, Formosa, and the China coast. If all went well, Mindanao would be assaulted on 15 November by General MacArthur, supported by the Pacific Fleet, and Luzon or Formosa would be assaulted on 15 February 1945. The object of taking Mindanao was to further the advance to Formosa either directly or via Luzon. The JCS directed that long-range planning be undertaken for assaults on all three objectives - Luzon, Formosa, and the China coast area - with General MacArthur's Staff undertaking the first, and Admiral Nimitz's staff the latter two. The Purposes of the Exercise The code name of Forager was assigned to the capture, occupation, and defense of Saipan, Tinian, and Guam. The Commander in Chief, Pacific had four principal purposes in mind in launching Forager. The obtaining of an island base from which the Japanese homeland could be bombed was the one appealing to all Services, although more strongly to the Army Air Force, since it would permit them to really pull an oar in the Pacific War. A second principal purpose was to obtain a base which would permit the isolation and neutralization of the Central and Western Carolines. This one appealed particularly to the Army as it was anxious to facilitate General MacArthur's movement to the Philippines, and this would be made more practical if, as he advanced, Japanese island positions on his right flank were isolated or neutralized. The other two principal purposes were primarily naval. The Navy thought it was highly desirable to have effective command of the sea in the general Marianas area, and thus a forward position on the flank of the Japanese communication lines to the Philippines and Southeast Asia. This was in order to harass or break these Japanese lines of communication. There also was a strong naval desire to secure a large base from which a direct amphibious assault could be launched against the Ryukyus, the Bonins, or the Japanese Homeland. The Nut Cracker A glance at the detailed chart and maps of Saipan, Tinian and Guam immediately indicates that the Marianas were quite a different cup of tea from Makin or Tarawa or Kwajalein or the other atolls which had been captured in 1943 and early 1944. Rather than small flat rims of coral, they were good sized islands with all the defensive possibilities which real fortification, rough terrain and tropical growth over large land masses can provide. And it is worth stating a second time that with the Marianas located over 3,000 miles from Pearl and something less than half that far from Tokyo, it would be far more difficult to establish there the prerequisites for a successful amphibious operation. These are: 1. Secure lines of communication to the zone of conflict. 2. Command of the seas around the objective. 3. Command of the air around the objective. It has to be kept in mind that an invader is most vulnerable as he hits the beaches. This is the transition period of an amphibious assault. Resources Three divisions, which had been earmarked for the sequential assaults on the Mortlock Islands and on Truk, were designated for the invasion of Saipan and the subsequent capture of Tinian. These were the Second and Fourth Marine Divisions, with the 27th Infantry, a National Guard unit from the State of New York, in reserve. They were to be mounted in the Hawaiian Islands, 3,000 miles away. For the assault on Guam, the Third Marine Division and the 1st Provisional Marine Brigade, made up of the 4th Marine Regiment, the 22nd Marine Regiment, and, after 10 July 1944, the 305th Infantry Regiment, were assigned. The units initially assigned were designated the 3rd Amphibious Corps on 15 April 1944, Major General Roy S. Geiger, USMC, Commander. They were to be mounted in Guadalcanal and the New Hebrides, 1,650 to 2,200 miles southeast of Guam. The 77th Infantry Division, training in the United States during the early planning period, was to be brought to the Hawaiian Islands by March, and alerted for a move on to the Marianas twenty days after Dog Day at Saipan. It could not be mounted for a Dog Day assault or as the Guam Reserve because of lack of transports and cargo ships. From this listing of participating troops, it is apparent that the Marianas was to be the biggest amphibious assault to date in the Central Pacific Campaign with three and two-thirds divisions designated for assault and two divisions designated for the Reserve. Forager, the Marianas campaign, was complicated. As Admiral Turner said: The Marianas Campaign, from an amphibious view point had nearly everything; great strategic importance, major tactical moves including successive troops landings on three enemy islands; tough enemy resistance of all kinds, including major Fleet battle; coordination of every known type of combat technique of the land, sea, and air; difficult logistic problems; and the build up of a great military base area concurrently with the fighting. Before the operational phases of the Marianas campaign are related, a few of the major changes in the administrative and organizational aspects of the Amphibious Forces, Pacific will be set down. Ships and Landing Craft and More Ships and More Landing Craft COMINCH, on 1 February 1944, assigned all attack transports, attack cargo ships, and landing ships and craft, in or destined to report to the Pacific Ocean Areas, to Commander Amphibious Forces, Pacific (Rear Admiral R. K. Turner). This broadened his command from the Fifth Amphibious Force in the Central Pacific to all the amphibious forces in the Pacific Ocean Area. On 8 March 1944, Vice Admiral Turner reported to CINCPAC for this additional duty which included command of all amphibious craft assigned to the First, Third, Fifth, and Ninth Fleets; the Amphibious Training Command; and the Army, Navy, and Marine Corps units currently assigned to those Amphibious Forces for training or combat operations. He was also responsible for the preparation and periodic correction of two Pacific Fleet publications entitled Tactics Orders, Amphibious Forces, Pacific Fleet and Current Doctrine for Amphibious Forces, Pacific Fleet. As the Amphibious Forces moved through the Gilberts and the Marshalls, some of the landing ships (LST's) and many of the landing craft (LCT's) were left behind to provide the necessary unloading lighterage at the island bases. There was a real need to reorganize the landing ships and craft which returned to Pearl with sizeable gaps in their organizations and provide appropriate division commanders, group commanders and flotilla commanders. The need was brought to the attention of CINCPAC and COMINCH, and the latter, on 30 March 1944, authorized remedial action. Thereafter, COMPHIBSPAC, acting under delegated authority, reorganized the LST's, the LCI's and the LCT's, generally on the basis of geographical location. This, as many skippers were quick to report, broke up many fine chains of command which had existed since the landing ships and craft were on the building ways back in the States. Soon afterwards, a more favorably-received step was taken. This was to provide adequate repair facilities for these craft even in the forward areas. In early April 1944, the first edition of Transport Doctrine, Amphibious Forces, U.S. Pacific Fleet was issued. This healthy sized document provided general transport doctrine as well as specific transport doctrine for all types of landing ships and landing craft. It was amended a dozen times before World War II was over, but it served to indoctrinate the tens of thousands of young Americans who were becoming amphibians. The Fifth Amphibious Force Staff Grows and Grows By the time the Fifth Amphibious Force was deep in its training to take the Marianas Islands, Vice Admiral Turner's Staff had grown to thirty officers. The number of officers attached to the staff for communications, intelligence and other specialty duties had increased to 56. The Chief of Staff had been advanced in rank to Commodore early in April 1944. Kneeding Flintlock into Forager Although Flintlock was termed a grand success, COMFIFTHPHIBFOR issued a 37-page letter, with comments on the operation and many suggestions for further improvements in the naval phases and naval techniques of the amphibious operations. On the other hand, the Commanding General, V Amphibious Corps, was reasonably satisfied, as this extract from his report indicates: Recommendations made and acted upon - as a result of the Gilberts offensive proved sound. In the attack of coral atolls, very few recommendations can be made to improve upon the basic techniques previously recommended and utilized in the Marshalls. From the time of the conquest of the Marshalls, the DUKW was the major small logistical workhorse of the Central Pacific Campaign, and as Admiral Turner commented: The Army's most important contribution to the technique of amphibious warfare. The Marianas The Marianas are a 450-mile long string of fifteen volcanic islands lying north and south between Latitudes 13 and 21 degrees north, and generally along the 145th parallel of east longitude. Guam is the southernmost of the island string. It lies a bit less than 1,400 sea miles south-southeast of Tokyo and 1,500 sea miles east of Manila. 101 miles separate Saipan, the second largest of the Marianas, from Guam. Tinian nestles up to Saipan and Rota is 37 miles northeast of Guam. Eleven smaller islands stretch 350 miles north of Saipan. Guam also is the largest of the Marianas, with a land area of 206 square miles. Saipan covers 70 square miles and Tinian only 38 square miles. Each of these three islands has both rock-ribbed hills and swampy valleys. Guam has half a dozen rugged peaks over a thousand feet high with the highest being Mount Lamlam of 1,334 feet. Saipan tops out in its center at Mount Tapotchau at 1,554 feet, while smaller Tinian, in general, is flatter with Lasso Hill of 564 feet its highest point. Tropical vegetation, in 1944, covered much of the islands, and there were marshes and rice paddies in the lowlands. The only useful harbors in the group are Apra Harbor in Guam and at Tanapag in Saipan. The latter is very small. The tide in the Marianas is negligible since it is less than 1.5 feet. Raising sugar cane, copra, bananas, and papayas were the principal activities of the natives in 1944. Seventy percent of Saipan was under sugar cultivation. The population of Saipan and Tinian was principally Japanese with a modest proportion of Chammorro's, while that of Guam was entirely Chammorro. Natural Defenses Saipan Looking at the three principal southern islands in 1944 from the amphibious assault viewpoint, it was seen that a barrier reef one to two miles off shore protected the west side of Saipan. The land sloped gently away from the beaches which were extensive but only 10 to 15 yards wide. On the east side, the beaches were narrow and the shores steep with many wave-cut cliffs. The north end and east side of Saipan, except for Magicienne Bay, were free of reefs. This bay provided no shelter from the prevailing trade winds and the Japanese, reputedly, had not used the bay because of this and the inshore reefs. Tinian Tinian had the same natural defenses as Saipan's east coast - healthy sized cliffs and very narrow shallow beaches. This would make the logistic support problem very difficult in the early hours of any assault landing. Guam The detailed information available during the 1944 planning period in regard to the beaches of Guam was good, because the Marines had studied the island from a defensive point of view during the pre-1941 period. The northern half of the island was easily defendable because of the high cliffs overlooking the beaches and the strong surf and rugged offshore reefs. The 868 Amphibians Came To Conquer whole east coast of Guam was marked by a 400-foot plateau and a narrow coastal flat. However, in the vicinity of Agana Bay near the capital Agana, there were some breaks in the long reefs on the western side of the island, and another break south of Orote Peninsula. This peninsula jutted out three miles into the western ocean and provided a lee for the beaches south of it. The Weather Prospects In a few words, the weather was warm, showery and generally overcast. The summer months are the rainy season, August being the wettest month with numerous thunderstorms and squalls. Typhoons are scarce around the Marianas but do occur. The monsoon winds blow in from the southwest in August and September; the trade winds blow from the northeast the rest of the year. So, from a weather point of view, the landings and early logistic support follow up had to be completed before the end of July, if the landings were to be made on the west coast of Saipan where the preferred beaches were located. The "generally overcast" type of weather meant that air reconnaissance would have photographic and observation problems. Japanese Reaction to Loss of Marshalls Admiral Koga, Commander in Chief of the Japanese Combined Fleet, made a visit to Japan from Truk soon after our seizure of Kwajalein and Eniwetok in the Marshalls, to Participate in military conferences. The Japanese High Command on 1 March 1944 took the decision to build up overseas personnel and material strength, construct fortifications with special emphasis on the Marianas and Western Carolines, and firmly defend their new "Secondary Defense Line." These important defensive steps were planned to be completed by April 1944, and except for planned aircraft and air bases they were largely in hand by the end of May 1944. A Japanese Central Pacific Area Force secret order captured during the Forager Operation indicated that, in the Marianas, Japanese plans contemplated a total of fourteen airfields and two seaplane bases adequate to handle 600 aircraft. In the Southern Marianas, by early June 1944, there were two Japanese airfields operational on both Saipan and on Guam, three operational airfields on Tinian and a surfaced runway on Rota. Additional airfields were in various stages of completion. There was a major Japanese seaplane base at Tanapag Harbor on Saipan. The Japanese Defenses Soon after arriving back in Pearl, and still not sure whether the next amphibious objective would be Truk or the Marianas, COMFIFTHPHIBFOR requested CINCPAC to provide air and submarine reconnaissance of the Carolines and Marianas to supplement that obtained on 22-23 February 1944, during the first air strikes against the Marianas. This was done by Navy PBYs, flying out of Eniwetok on 18 April and 25 April 1944, and again on 7 May and 29 May 1944. The submarines of the Pacific Fleet during April 1944 gave their particular attention to prospective landing beaches with rewarding results. The Japanese on Saipan The natural defenses of Saipan, the first island in the Marianas to be assaulted, were considerable. The east coast was largely free of fringing reefs except around the largest bay - Magicienne Bay - but the beaches were narrow - and more importantly from the Marines' point of view - the shores back of the beaches were steep, rugged and easily defended. The west coast of Saipan was lower and the land back of the beaches sloped gently upward, which was fine from the Marine point of view. But, with the exception of a gap off Charan Koa and the entrance to Tanapag Harbor, a barrier reef protected the whole west coast of Saipan. On Saipan the Japanese had an island 12 3/4 miles long and 5 3/4 miles wide to defend. In comparison, the later objectives, Tinian was 10.5 miles long and markedly narrower than Saipan, while Guam was 32 miles long and 4 to 8 miles wide. Beginning in March 1944, the Japanese not only rapidly built up their defenses and their defensive forces in the Marianas, but, additionally, reorganized the command structure which controlled the area. The Fourth Fleet which had held the bag during the loss of the Gilbert Islands and the Marshall Islands was downgraded to controlling only the naval garrisons in the Eastern Carolines (including Truk) and the bypassed garrisons in the Marshalls, all of which were dying on the vine. A new command directly under the Combined Fleet, called the Central Pacific Area Fleet, was established under the command of Vice Admiral Chuichi Nagumo, IJN, who had been commander of the Japanese naval force making the surprise attack on Pearl Harbor. Vice Admiral Nagumo maintained his Headquarters on Saipan and was present and accounted for when the assault commenced. He controlled the naval garrisons in the Western Carolines where the important Palau Islands were located, as well as the Marianas and the Bonins where Iwo Jima was located. The responsibility for the defense of individual islands rested upon the senior Army or Naval officer assigned to that island. By and large, the Japanese Army was able to place the senior officer on each island. Saipan also housed the Japanese Army command for all Japanese Army forces in the Mandates. This was the 31st Army. Its Commanding General was Lieutenant General Hideyoshi Obata. He lived a few days longer than others because he was absent from his command and in the Palau Islands for a conference when we landed 01115 June 1944. His senior subordinate, Lieutenant General Yoshitsugu Saito, IJA, Commanding the 43rd Division, took over Obata's duties and fought the good fight. All during the months of March, April, May, and early June, the Japanese poured troops into the Marianas. They had their troubles doing this as the following extract from an interrogation of Commander Tadao Kuwahara, IJN (Retired), Convoy Commander for part of the movement of the 43rd Division, will show: I left Tateyama for Saipan on 30 May 1944 with a convoy of seven vessels and four escorts. Three of the ships were transporting 10,000 troops to Saipan. This was the last convoy to go to Saipan . . . . The convoy was attacked by submarines on the 1st through the 6th of June, all attacks occurring at about 1500-1600. The submarines had been following another convoy bound for Japan. When the two convoys crossed, the submarines turned around and followed my convoy . . . . On 4 June, the convoy was attacked simultaneously from the two front quarters and the port after quarter. Katsuya Maru was sunk. On 5 June, we were attacked again from two sides and Takaoka Maru and Tamahime Maru were sunk. On 6 June we were attacked once more on two sides, simultaneously. Kashimaran Maru, carrying aviation gasoline was hit during this attack and exploded. About an hour later, another attack sank Haore Maru. Of the troops of the three troop transports . . . 80% were saved . . . . Eighty percent of the Japanese troops of this particular movement were saved but their heavy equipment including guns and ammunition were all lost. As was reported by despatches from Saipan to Japanese Headquarters in Tokyo: The shipwrecked units are 3rd and 4th Independent Tank Companies, 14th and 17th Independent Mortar Battalions, 3 aviation units, etc., and have no use as fighting units; the infantry are without hats and shoes and are in confusion. And, while the Japanese rapidly built up the defenses of Saipan, there was much they didn't do. The Commander in Chief, Pacific Ocean Areas in his Operational Report on the defenses of Saipan, based on data determined after the occupation, wrote: Subsequent to the capture of Saipan, an inspection of its defenses was made by the Engineering Section of the Expeditionary Troops. Information was obtained from an important prisoner of war who had been the former Intelligence Officer of the Japanese 43rd Division and from captured documents . . . . The prepared defenses of Saipan were amazingly inadequate and incomplete . . . . Not a single battery position or fortification inspected was entirely complete . . . . In the Garapan Naval Depot, the following guns were found: 3 5" coast defense guns, 1 140-mm coast defense gun, 32 120-mm dual purpose guns, 6 200-mm mortars. Guns implaced ready to fire: 6" 120-mm 200-mm Total 8 20 4 32 * * * * * It can be seen that only slightly more than one-third of the heavy coast defense and dual purpose guns that were available on the island had been completely mounted and made ready for firing. Japanese Defense Doctrine The Japanese documents captured in previous amphibious operations had always stressed the Japanese island defense doctrine of "destroying the enemy at the beaches," or in other words during the most difficult period of the amphibious operations - the transition period from naval war to land war. It was widely anticipated that since the Marianas were quite different islands than those in the coral atolls, that the Japanese defensive pattern would change. But it didn't. A captured document on Saipan read: It is expected that the enemy will be destroyed on the beaches through a policy of tactical command based on aggressiveness, determination and initiative. The Japanese Fleet Again Retires Westward When Task Force 58 raided the Palau Islands at the end of March 1944, the Japanese Combined Fleet once again retreated westward, this time to Tawi Tawi Harbor in the Sulu Archipelago in the Southwest Philippines. It was operating in this area, 1,600 miles away from the Marianas, when the Joint Expeditionary Force moved in to assault the Marianas. Worried about the defense of western New Guinea, a good sized detachment of the Combined Fleet was under orders early in June 1944 to support a Japanese amphibious assault to recapture Biak Island off northwestern New Guinea. Japanese land-based planes from the Marianas were ordered down south to Halmahera to support the operation. The Japanese task force for this assault, Operation KON, was actually well assembled at Batjan in the Moluccas (southwest of Halmahera, four hundred miles south of Mindanao) by 11 June. Reports of the TF 58 raids on the Marianas late on that day raised doubts in the minds of the Japanese as to whether the Marianas were being raided or whether they were a United States amphibious assault objective. Upon receipt of news on 13 June that battleships were bombarding Saipan, the Japanese assault on Biak was cancelled by Admiral Toyoda, Commander in Chief Combined Fleet. He had succeeded to command the Combined Fleet upon the death in a plane accident of Admiral Koga. The cancellation was the the first of many pleasant dividends from Forager. Organizing for Forager The tremendous size of the Forager Operation began to become a reality when the Commander Pacific Ocean Areas in his basic order directed: All major Commanders in the Pacific Ocean Areas will support this operation. To give further orientation on the titular nomenclature used in the Central Pacific it should be recorded that when Admiral Spruance was directed to conduct the wide-ranging Forager Operation it was as Commander Fifth Fleet rather than as Commander, Central Pacific Task Forces. The Expeditionary Troops included the two Landing Forces, each approximately the equivalent of a corps command, as well as the Expeditionary Troop Reserve and the Garrison Troops. Lieutenant General Smith retained command of the Northern Landing Force, but in this task used a staff separate from the one which functioned with him in the whole Expeditionary Troop command. Major General Roy S. Geiger, USMC, commanded the Southern Landing Force at Guam. The two assault Landing Forces initially totaled 127,500 men, with 71,000 for Saipan and 56,500 for Guam. Commander of the Saipan troops in the Expeditionary Reserve (CTG 56.3), the 27th Infantry Division, was Major General Ralph Smith, AUS. Major General Andrew D. Bruce, AUS (CTG 56.4), commanded the 77th Infantry Division, initially designated "In general area reserve" but planned to be used for the Guam landings. As it turned out, the "general reserve" was embarked from Pearl Harbor in two echelons based on the availability of transports. Captain J. B. Heffernan (1917) embarked the first echelon, the 305 Regimental Combat Team from the 77th Division, in a division of transports on 2 July, and Captain H. B. Knowles (1917) embarked the second echelon, which was the remainder of the 77th Division in two divisions of transports on 9 July. In the original plan it was estimated that the Joint Expeditionary Force would complete its missions for Forager about Dog Day plus 40 (July 25th) and that the entire movement of garrison forces and equipment would be completed about Dog Day plus 80 (September 3rd). The first estimate turned out to have been optimistic.