Part VI: Conclusion
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Chapter 1: Amphibious Doctrine in World War II1
The Genesis
One would not exaggerate by saying that amphibious warfare was the primary offensive tactic in the American conduct of the Pacific War. Simply defined, an amphibious assault is “an operation involving the coordinated employment of military and naval forces dispatched by sea for an assault on a hostile shore.”2 In his final report of the war to the Secretary of the Navy, Admiral King stated:–
The outstanding development of this war, in the field of joint undertakings, was the perfection of amphibious operations, the most difficult of all operations in modern warfare. Our success in all such operations, from Normandy to Okinawa, involved huge quantities of specialized equipment, exhaustive study and planning, and thorough training as well as complete integration of all forces, under unified command.3
Marine Corps interest in what is termed amphibious warfare may be said to have begun as early as 1898, when, in the Spanish-American War, Lieutenant Colonel Robert W. Huntington’s battalion of Marines landed at Guantanamo, Cuba, to seize a major naval base for fleet operations in the blockade of Santiago.4 In the years following this landing, the advanced base concept envisioned the establishment on a permanent basis of a force capable of seizing and defending advanced bases which a fleet could employ to support its prosecution of naval war in distant waters. According to the theory of how advanced base operations were to be conducted, primary emphasis was on the defense of the base. There was apparently no consideration in the pre-World War I period of the feasibility of large scale landings against heavily defended islands, which, of course, was the nature of much of the amphibious warfare in the Pacific in World War II.
As the international commitments and influence of the United States increased during the early years of the 20th century, the requirements for military and strategic planning grew apace. American interest in Latin America and U.S. participation in World War I accelerated
the need for the preparation of long-range programs, and the Marine Corps was not exempted from having to look to the future. Although expeditionary service in revolt-torn Latin America constituted a heavy and continuing drain on the services of the Marine Corps and forced it to focus attention on that area, a few farsighted military strategists, such as the brilliant Major Earl H. Ellis, directed their thoughts to the Pacific and to the prospect of war between the United States and Japan.
In the general distribution of the spoils following World War I, Japan was given the mandate over former German possessions in the Central Pacific. Thus, the strategic balance in that area was changed drastically in favor of Japan, which now had authority over a deep zone of island outposts guarding its Empire. Once they were fortified and supported by the Japanese fleet, they would provide a formidable threat to the advance of the United States fleet across the Pacific if a war broke out.
Ellis was one of the first to recognize the danger posed by the strategic shift in the Pacific. This awareness influenced him to modify his earlier ideas about the nature of a war with Japan and in 1921 he submitted his new thoughts in the form of Operation Plan 712, “Advanced Base Operations in Micronesia.” He foresaw operations for the seizure of specific islands in the Marshall, Caroline, and Palau groups, some of which Marines actually assaulted in World War II. His views were generally shared by the Commandant, Major General John A. Lejeune, and other high ranking Marine officers.
The Marine Corps did little in the area of amphibious planning and training during the late 1920s and early 1930s because in those years it was busily engaged in the pacification of Nicaragua, Haiti, and Santo Domingo, and in protecting American lives and interests in the midst of the unrest in China. It was thus precluded from engaging in large-scale amphibious exercises during these years. None could be held in any case because military appropriations were slim. Additionally, the Navy was more interested in preparing for traditional fleet surface actions. Nevertheless, much thought and study was given to amphibious logistic supply in the Navy-Marine Corps maneuvers at Culebra in 1924 and during the joint Army-Navy-Marine Corps maneuvers at Hawaii in 1925. Out of these meager efforts, the genesis of present amphibious doctrine appeared early in the academic year 1930–1931, when the Commandant of the Marine Corps Schools directed a committee of four officers—Majors Charles D. Barrett, Pedro A. del Valle, and Lyle H. Miller, and Lieutenant Walter C. Ansel, USN—to prepare a manual embodying existing knowledge concerning landing operations. Although never published, Marine Corps Landing Operations, as it was entitled, comprised the first formal effort to assimilate current amphibious doctrine. As General del Valle recalled:–
... the boss man in that show was Charlie Barrett, who was a brilliant officer, and the rest of us were ‘makee-learnee’ and all that we did was study the meager historic records ... and semi-historic records that existed. I remember that I had read about the Mesopotamian
campaign of Sir Charles Townshend, and he gave me some of the principles of a landing attack that we incorporated into this original study. ...5
After Major Barrett, as general chairman of the committee, had blocked out the general form the manual was to take, he was transferred to Headquarters Marine Corps and his place was taken by Major DeWitt Peck, who, in addition, was head of the Tactical Section of the Marine Corps Schools. Major Peck:–
... wrote the basic chapter ... and parceled out the other chapters to the appropriate school instructors, artillery to the artillery] instructor, etc. As the chapters were finished [Peck] as editor, coordinated the whole. ...
Upon approval of the CO of the Schools, the manual was sent to HQMC where it was reviewed, I believe, by Barrett and [Major Alfred H.] Noble. The only important change they made was in the handling of beach and shore parties, reversing the school concept.6
The groundwork prepared by these officers at the Marine Corps Schools resulted in further study of the subject at Quantico and elsewhere. Meanwhile, the Fleet Marine Force was established in September 1933, and became increasingly important in Marine Corps training, planning, and thinking.7 Immediately following the activation of the FMF, it became necessary to prepare a textbook which would incorporate the theory and practice of landing operations for the use of the infant tactical organization. Work on this text began at the Marine Corps Schools in November 1933, when all classes were suspended and both faculty and students were assigned the duty of writing a manual that would present in published form a detailed account of the doctrine and techniques to be employed in training for and conducting amphibious assault operations.
The final result of this crash program appeared in January 1934 under the title Tentative Manual for Landing Operations. The contents and title of the manual were revised several times in the following years, and the Navy accepted it as official doctrine in 1938, when, entitled Tentative Landing Operations Manual, the book was reprinted and distributed as Fleet Training Publication 167 (FTP-167). Three years later, the War Department recognized the worth and potential of amphibious tactics and published the substance of the work as Field Manual 31–5.
Army interest in amphibious assault tactics had resulted earlier in the participation of the 2nd Provisional Army Brigade (18th infantry and two battalions of the 7th Field Artillery) in Fleet Landing Exercise Number (FLEX) 4 in 1938. Not until 1941 did the Army again take part in a FLEX or evince any overt
interest in amphibious warfare. It was in this year that joint amphibious training of Army, Navy, and Marine Corps organizations was first conducted on the east coast. Under the experienced guidance of Major General Holland M. Smith, commander of the Amphibious Corps, Atlantic Fleet, and his staff composed of officers from the three services, the 1st Joint Training Force (1st Marine Division and 1st Infantry Division) conducted maneuvers at Culebra and later at Onslow Beach, North Carolina. Following in 1942, the 9th Infantry Division joined the 1st Marine Division in landing exercises on the east coast. Meanwhile, other Army divisions were similarly involved in the west coast training together with FMF units and learning the fundamentals of amphibious warfare. The results of this training were thoroughly demonstrated throughout the war wherever Army divisions made amphibious assaults.
Lessons learned and gradual advances made in the period 1934–1940, and the refinements that appeared in the fleet landing exercises conducted during the prewar years, placed at the disposal of United States forces at the beginning of World War II a body of tactical principles forming a basic amphibious doctrine. At Guadalcanal, Marines were the first to put to the test of war this doctrine, and found it practicable. General Vandegrift, who commanded the Guadalcanal assault troops, later wrote:
We were as well trained and as well armed as time and our peacetime experience allowed us to be. We needed combat to tell us how effective our training, our doctrine, and our weapons had been. We tested them against the enemy and found that they worked.8
The two key words in General Holland Smith’s definition of amphibious tactics noted above are “coordinated” and “assault.” In the formal body of amphibious doctrine presented in early 1934, the Marine authors had recognized that an amphibious operation was a joint undertaking of great complexity and that the landing of troops on a hostile shore had to be accomplished as a tactical movement. The steps leading to a successful landing operation included an approach, deployment, and assault by the landing force following an adequate preparatory bombardment and accompanied by the effective supporting fires of surface and air forces. Basically, this is how Allied amphibious operations were conducted in World War II and since.
Also basic to the conduct of an amphibious assault was the organization, founded on well-established concepts, of the amphibious task force and its major elements. Generally, such a force was comprised of the following: a transport group, a fire support group, an air group, a mine group, a salvage group, and a screening group, all naval units; and a landing force, composed of Marine units for the most part. The latter was conceived as a mobile striking force containing self-sufficient combat elements that could be employed with a maximum degree of flexibility.
The nucleus of the landing force was usually the Marine division, which was
often reinforced by corps troops, and sometimes Army units. In the division were three infantry regiments, an artillery regiment, and division, special, and service troops, the composition, organization, and strength of which underwent several changes in the course of the war. According to established doctrine, the assignment to the Marine landing force of troops and equipment for an amphibious operation was based on the impending mission and the lift capability of the assault transports carrying the troops to the target.
Not all phases of amphibious operations were emphasized during the fleet landing exercises before 1940. Basic logistic planning was relatively simple in this period because there was little equipment to embark and hardly any assault shipping worthy of the name to embark it in, especially when compared to conditions in the war years. One logistics shortcoming which was brought to light following the early assault operations in the Pacific concerned the over-the-beach handling of supplies. While not completely resolved, this problem was considerably eased with each succeeding operation as the planners attempted to correct the mistakes of previous landings.
In reviewing the development of amphibious tactics, General Holland M. Smith, who has been called the “Father of Amphibious Warfare,” stated:–
Amphibious preparedness in the two years prior to Guadalcanal consisted on the one hand of full-scale production of the materials which had been found suitable for landing operations in the experimental period before 1940 and on the other of training military and naval personnel to use that materiel in accordance with the tactics and techniques, which had also been developed, in war.9
Faced with the imminence of war, Congress made adequate funds available for a speedup of defense preparations. Some of this money was allotted to the Navy and Marine Corps, which then began to eliminate personnel and materiel shortages as rapidly as possible. The most important task facing the Marine Corps as it prepared for the world conflict certain to erupt was to train troops in amphibious tactics utilizing the doctrine, equipment, and materiel then available.
As General Vandegrift commented, Guadalcanal proved Marine tactics were sound. The subsequent development of amphibious tactics following later landings and combat ashore in the Pacific did little to change basic doctrine, but did serve to teach Americans how to land more troops and materiel on the beach in a shorter period of time and at less cost. In the course of the war, existing techniques were perfected and refined at the same time that new solutions (JASCO, air support control, and underwater demolition teams) and the employment of new equipment (radar, landing ships and craft, amphibious command ships, and escort carriers) were developed and integrated with the basic amphibious warfare doctrine to eliminate old problems.10 It was readily apparent that, no matter how sound Marine tactics were, they were ineffective unless dynamic, intelligent, and well-informed
commanders and highly trained and disciplined troops employed them aggressively, vigorously, and resourcefully. The Navy and Marine Corps learned lessons in every assault operation that they conducted during the war; in the final analysis, the experiences gained in one landing helped to achieve the successes in each following one.
The Pacific War may be roughly divided into three periods,11 during which amphibious tactics were developed and gained optimum results. The first or defensive period began with the attack on Pearl Harbor and lasted until the landings on Guadalcanal and Tulagi. The second, a period of limited offensives, began with the Guadalcanal operation; the third was an offensive period heralded by the Tarawa invasion in November 1943. In the opening year of American offensive operations, United States commanders learned that close cooperation between landing force and naval staffs through the planning and training phases for a landing and during its execution was vital to its success.
Command Relations
In World War II “joint forces fought in assault on a scale never before dreamed of. So much combined effort called for the highest possible degree of coordination.”12 For the Marine Corps, the delineation of command responsibilities between the amphibious force commander and the landing force commander was an important factor in the success of the advance across the Pacific.
The chain of command in a force established to conduct an amphibious assault was relatively simple, at least in theory, and Guadalcanal was the testing ground for this facet of amphibious doctrine. According to FTP-167:–
d. The attack force commander will usually be the senior naval commander of the units of the fleet comprising the attack force. … Provision must be made in advance for continuity of command within the landing area during the course of the operation.13
And this was all that FTP-167 said about command relations. Essentially, the naval amphibious force commander would have the primary authority for decisions affecting either the landing force or the various support groups, each of which would have co-equal command status and parallel command functions under his direction. The pattern was thus set in the Guadalcanal landing for the concept of command relations—worked out in peacetime—to be employed in a combat situation for the first time.
At Guadalcanal, Major General Alexander A. Vandegrift, Commanding General,
1st Marine Division, and the landing force commander for the operation, was subordinate to Rear Admiral Richmond K. Turner, Commander, Amphibious Force, South Pacific (Phib- ForSoPac), and amphibious force commander for the same operation. A major source of disagreement which rose between Turner and Vandegrift was based on their differing concepts of Vandegrift’s command functions and responsibilities once the general had landed and assumed responsibility for the conduct of operations ashore.
Even before the order for the Guadalcanal operation had been distributed, the command relationship between these two leaders derived from the following paragraph of the order which established Turner’s command in April 1942:
IX. Coordination of Command
(a) Under the Commander, South Pacific Force, Commander of the South Pacific Amphibious Force will be in command of the naval, ground and air units assigned to the amphibious forces in the South Pacific area.14
Further augmenting this relationship was a clause in the JCS Directive of 2 July 1942, setting forth the military aims of the moment for the war against Japan in the South Pacific and Southwest Pacific areas, and which stated:
Direct command of the tactical operations of the amphibious forces will remain with the Naval Task Force Commander throughout the conduct of all three tasks.15
In the planning for and actual conduct of operations at Guadalcanal, Turner’s forceful personality and character had an effect on each decision made. General Vandegrift maintained that the commander trained for ground operations should not be subordinate to the local naval amphibious force commander with respect to the conduct of the land battle and the disposition of the main force and reserves given the responsibility to fight it.16
Concerning these differences of opinion, Major General DeWitt Peck, who was War Plans Officer for the Commander, South Pacific Force (ComSoPac), wrote: “It might be noted that in questions of command relationship, General Vandegrift’s position was supported by ComSoPac. I believe, however, that a definite directive should have been issued when the question first
arose.”17 Continuing, General Peck recalled:
... two points of difference between Vandegrift and Turner in particular. After the successful landing at Guadalcanal and the consolidation, Turner wanted Vandegrift to station marine detachments at several points along the NE and NW shores of the island which were likely landing places for Japanese reinforcements. Vandegrift refused to make this dispersion of his force. At another time Turner wanted Vandegrift to form another Raider Battalion, composed of selected personnel from the Division. Vandegrift refused. It would weaken the Division both in personnel and morale to form an ‘elite’ organization. In fact there was considerable question in SoPac as to the efficacy and wisdom of having raider battalions.18
When the Commandant of the Marine Corps, Lieutenant General Thomas Holcomb visited Guadalcanal in late October 1942 and questioned Vandegrift about the local situation, the 1st Marine Division commander related his problems and said “the quicker we get the Navy and particularly Kelly Turner back to the basic principles of FTP-167 ... the better off we are going to be.”19
At the request of Admiral Halsey (ComSoPac) on 23 October, Vandegrift accompanied the Commandant and his party in a flight to Noumea, New Caledonia, for a conference with Halsey and his major commanders concerning Guadalcanal. During this conference Holcomb raised the question of command relationships in the amphibious force and made certain recommendations concerning organizational and command relationship changes in Turner’s force. After his retirement, Admiral Turner later told his biographer that he had not been adverse to these changes.20
After approval had been given by Halsey, Nimitz, and King, the command structure in Amphibious Force, South Pacific, was changed as follows on 16 November 1942:
a. All Marine units were detached from PhibForSoPac.
b. All Marine Corps organizations in the South Pacific Area, except Marine Corps aviation, regular ships’ detachments, and units in the Ellice Islands and the Samoan Defense Group, were assigned to I Marine Amphibious Corps.
c. For coordination of operations, joint planning would be conducted by
CG, IMAC, and ComPhibForSoPae under the control of ComSoPac.21
In addition, it was determined that in the future, after the landing force commander had landed, control of the troops ashore would revert to him in his capacity as commander of a task force established in the operation order to conduct the shore phase of the operation An alternative to this was that Marine Corps units would revert to Marine Corps command when and as directed by ComSoPac or, as the Allies tightened the ring around Japan, by the area commander.
Although the pattern embodied in this directive was the one followed throughout the war in the Pacific with but few modifications, it took a little while before the concept of separate functions prevailed. As Admiral Spruance’s former chief of staff recalled:–
The problem of the transfer of responsibility from the Commander Joint Expeditionary Force to the Commander Expeditionary Troops continued to plague Admiral Turner and General [Holland] Smith until an agreement was reached during the planning for ‘GALVANIC.’ [The invasion of Tarawa in November 1943].
I was not a witness to any arguments the two commanders may have had, but each came to me privately and complained about the other. ... My job was to reassure them, quiet them down, and try to solve their differences. I could get no help from Admiral Spruance. His attitude was ‘They both know what I want and they will do it. There is no need of prescribing definitely a solution.’ I insisted that it was essential to include in our order a definite statement of the transfer of responsibility, not only to satisfy the two commanders but so that the entire force would understand.
I continued to draft proposed paragraph 5s [pertaining to command] of our operations plan until I finally reached a wording that was satisfactory to both Turner and Smith.
I have not got the plan before me but my notes indicate that para. 5 read in part like this:
‘The Commander Joint Expeditionary Force commands all task organizations employed in the amphibious operations at all objectives through inter-related attack force commanders. The Commanding General Expeditionary Troops will be embarked in the flagship of the Commander Joint Expeditionary Force or stationed ashore when the situation requires, and will command all landing and garrison forces that are ashore.
Landing Forces, after their respective commanders have assumed command on shore, will be under the overall command of the Commanding General Expeditionary Troops.
Commander Joint Expeditionary Force is designated as second in command of this operation.’
There seemed to be no difficulty in accepting the provision that the landing force commanders would inform their respective task group commanders when they assumed command on shore.
Although Turner and Smith disagreed with much ill humor during the planning stages of GALVANIC, FLINTLOCK [the Marshalls landings], and FORAGER [the Marianas campaign], the minute they were embarked together in the flagship of the Comdr. Joint Expeditionary Force, friction disappeared and cooperation and collaboration was excellent.
The command arrangements established for GALVANIC set the pattern for FLINTLOCK
and FORAGER, and no further problems arose.22
Logistics
Another important lesson learned during the first year of the American offensive in the Pacific was that the logistical aspect of an amphibious operation was as vital to the success of a landing as were the assault tactics employed to reach and stay on the shore. Like the negative influence of the Gallipoli debacle on the evolution of so many other facets of amphibious doctrine, the failure of basic logistics planning during this World War I campaign spurred Marine planners on to develop sound logistical theory and techniques. Despite all efforts to the contrary, however, most if not all logistical problems that conceivably could occur during an amphibious operation cropped up in the preparations for and later at Guadalcanal.
The key to amphibious logistics planning developed by the Marine Corps in the prewar period was the “combat unit loading” of transports. This practical process involved the sequential loading of supplies and equipment in order to support the anticipated tactical scheme ashore. Combat loading was finally refined to the point where, if possible, all material belonging to a single organization was stowed in the same part of a ship. Because the tactical requirements for each amphibious assault were different, however, combat loading could not be standardized, and each load had to be planned by someone knowledgeable in logistics and familiar with the scheme of maneuver for the assault phase of the operation.
Trained to cope with the specialized nature of amphibious logistics and versed in all of its myriad details was the Transport Quartermaster (TQM), a Marine officer assigned to duty aboard each amphibious assault ship. He was required to be familiar with not only the weight and dimension of each item of Marine issue that might conceivably be taken into combat, but also every characteristic of the particular ship to which he was assigned. The TQM therefore had to become familiar with the exact location of all holds and storage spaces and their dimensions in cubic and square feet. Because modifications, not shown in ships’ plans, had often been made in troop cargo space of the vessel, the TQM was required to obtain an accurate remeasurement of holds, their hatches, and loading spaces.
The Marine Corps had acquired some, but not enough, practical experience in combat loading during fleet landing exercises held between 1935 and 1941. The lack of suitable transports and the uncertainty at times as to ports of embarkation and dates of availability of ships limited the full application of these doctrines in practice and prevented the Marines from gaining a real appreciation of what combat loading would be like under wartime conditions.
This lack was evident during the preparations for Guadalcanal. When the 1st Marine Division left the United States, it was headed for New Zealand, the staging area rather than the target, and most of the ships transporting division units were loaded
organizationally.23 The reason for this was because General Vandegrift and his planners had been told that the division was to “be the nucleus for the buildup of a force which would be trained for operations which might come late in 1942.”24 When 7 August was announced as the date for the invasion of Guadalcanal, a D-Day that was much earlier than had been expected, the division had to unload its ships at Wellington and immediately reload them for combat. Reloading was expedited and went relatively well for all groups except one, which found the Ii-day period required to accomplish this task something akin to a nightmare.25
At the objective, the inability of the landing force to relieve the congestion on the beaches, as men and supplies poured ashore, was as great and insoluble a problem during the war as it had been in the prewar landing exercises. Before World War II, no separate shore party organization had been established within the T/O for a Marine infantry division, with the result that labor forces had to be drawn from the tactical units for this purpose. The mission of the latter was thus affected adversely.
In the prewar years, when a simulated enemy was introduced to add realism to a fleet landing exercise, it proved difficult to achieve the requisite order and control of the beaches. In recognition of this problem, early amphibious warfare doctrine provided for the establishment of a beach party, commanded by a naval officer entitled a Beachmaster, and a shore party—a special task organization-commanded by an officer from the landing force. Such primarily naval functions as reconnaissance and marking of beaches, marking hazards to navigation, control of boats, evacuation of casualties from the beach, and the unloading of landing force materiel from the boats were assigned to the beach party. The duties of the shore party encompassed such functions as control of stragglers and prisoners, selection and marking of routes inland, movement of supplies and equipment off the beaches, and assignment of storage and bivouac areas in the vicinity of the beach. The Tentative Landing Operations Manual did not stipulate the strength and composition of the shore party, but only stated that it would contain detachments from some or all of the following landing force units: medical, supply, engineer, military police, working details,26 communications, and chemical warfare. Although the beach and shore parties operated independently, the manual called for their
commanders and personnel to observe the fullest degree of cooperation.
The solution to these deficiencies was found in 1941, when, based on the recommendations of Major General Holland M. Smith, a joint board consisting of Army, Navy, Marine Corps, and Coast Guard officers recommended to Rear Admiral Ernest J. King, Commander in Chief, Atlantic Fleet, that: (1) as a component of the landing force the beach and shore parties be joined together under the title Shore Party; (2) the beach party commander be designated both as the assistant to the shore party commander and as his advisor on naval matters; and (3) the responsibility for unloading boats at the beach be transferred from the naval element to the landing force element of the shore party.27
These changes were officially adopted on 1 August 1942 as Change 2 to Fleet Training Publication 167. Earlier that year, the size of the Marine division had been increased by adding a pioneer (shore party) battalion of 34 officers and 669 enlisted Marines. The T{O change was made on 10 January 1942, a date too late for the personnel concerned to acquire practical experience in large-scale exercises, where the techniques of handling vast quantities of supplies and the adequacy and strength of the new organization could have been tested.
At Guadalcanal, where logistical doctrine was put into practice, some glaring deficiencies were uncovered. To begin with, at that critical point in the war, the number of ships available for the operation was limited, necessitating a careful screening of the landing force equipment that was to be carried to the target. No gear that was in excess of tactical requirements could be loaded in assault shipping, nor was there enough hold space for all of the division organic motor transport. Most of the quarter and one-ton trucks were loaded aboard ships, but 75 percent of the heavier rolling stock was left behind with the rear echelon. When finally embarked, the Marines carried supplies for 60 days, 10 units of fire for all weapons, only enough individual gear to live and fight, and less than half of the vehicles of the division.
The Guadalcanal operation also demonstrated that an increased number of TQMs was needed to supervise all phases of loading and embarkation. In addition, events showed that boat crews well trained in seamanship and small-craft handling were required for the rapid unloading of ships, movement to the beach, and the return to the ships for other loads of cargo. Although this phase of assault landings was improved somewhat during the course of the war, comments concerning the operations of boat crews at Okinawa give rise to the observation that even at the end of the Pacific fighting there was still considerable room for improvement.28
A primary source of concern at Guadalcanal on D-Day and after was the slowness with which supplies were moved from the landing craft to the beaches and then to supply dumps inland. Quite simply, General Vandegrift
was faced at this critical point of the operation with a manpower shortage that had been predicted during the planning phases. In view of the uncertainty of the situation on a hostile beach, he believed that he could not spare men from combat units to augment the 500 Marines in the 1st Pioneer Battalion. The mounting stack of supplies on the beaches offered a lucrative target to Rabaul-based Japanese aircraft, but fortunately for the American forces ashore, the enemy concentrated on shipping in the transport area rather than materiel on the beaches. “ ‘Had the Japanese set fire to the supplies towering high on the Guadalcanal beachhead,’ to quote Vandegrift, ‘the consequences might well have been incalculable and ruinous.”29
Although enemy threats to the beachhead became negligible as the war progressed—that is, with the exception of the period of the Kamikazes—the logistical problems inherent in an amphibious assault landing never completely disappeared. Even under optimum conditions, such as those that existed on L-Day at Okinawa where there was no opposition to the landing, logistics problems continued to crop up from the very inception of an operation and were among the most difficult that the invasion force commanders had to solve. Quick and easy solutions were seldom if ever within grasp, for amphibious logistics has always been an immense and complex factor.
The Guadalcanal landings began the second or limited offensive period of the war in the Pacific. “So limited was it at first, that all of our efforts for several months were exerted primarily to hold what we had taken at Guadalcanal.”30 Operations in this second period were conducted chiefly in the Solomons–New Britain—Eastern New Guinea area and may be said to have lasted until November 1943. As one student of military history has written, the primary lesson of Guadalcanal “was that without the FMF, the operation could never have happened.”31
The United States entered the offensive period in November 1943 when the Central Pacific campaign opened with the Gilberts operation. This phase of the war was marked by growing American strength as new ships joined the fleet and additional troops became available. In November 1942, there were 69,320 Marine ground troops in the Pacific; this number increased to 100,845 a year later.32 Marine aviation strength increased proportionately. In this third war period, vast forward area bases were constructed from which these growing forces could mount and stage for future operations. Although the war in the South Pacific was primarily a holding action, which in the end became fully offensive in character, the Central Pacific campaign was a true offensive from the outset. The terrain of the targets here was entirely different from that experienced in the South Pacific, and the targets themselves were not only a series of “a
tiny, isolated, completely and densely fortified atolls or small islands”33 but also larger islands such as those found in the Marianas. In the conduct of the fighting in the Central Pacific and in the selection of targets, many of Ellis’ prophecies of the 1920s became reality.
It has been accurately stated that:
If the battles of the South Pacific proved that the Fleet Marine Force was ready for war, those of the Central Pacific demonstrated its grasp and virtuosity in amphibious assault. Except for Okinawa—which was really not a part of either South or Central Pacific campaigns—the entire roll of Central Pacific battles, from Tarawa to Iwo Jima, was by necessity a series of sea-borne assaults against positions fortified and organized with every refinement that Japanese laboriousness and ingenuity could provide. To reduce such strongholds was truly amphibious warfare à l’outrance [to the utmost]—the assaults which the Marine Corps had foreseen and planned for during the decades of peace.34
Between the invasions of Guadalcanal on 7 August 1942 and of Tarawa on 20 November 1943, Marine forces had been involved in assault operations in the Central and Northern Solomons. During the first year of offensive operations, and indeed until the end of the Pacific War, amphibious warfare doctrine was modified without seriously affecting basic principles. Two primary factors generated these modifications-increased American production and refinement of existing techniques in amphibious operations. Each of these factors had far-reaching influence on the reassessment and transformation of the following essentials of an amphibious operation:–
1. Preliminary preparation of the target [by air and naval gunfire].
2. [Air bombardment and naval gunfire] in close support of the landing.
3. Logistic support of the landing.
4. Landing craft.
5. Landing force communications.
6. Assault techniques and tactics.35
Amphibious assaults were uniformly successful throughout the course of operations in the Pacific because two of the principles of war—surprise and concentration of forces—were generally followed. In the final period of the war, it became not only practicable but possible to subordinate the former to the latter because American naval and air forces had gained control of a vast area above and surrounding the targets. Consequently, objectives were sealed off and the enemy could not reinforce a garrison in the face of an impending American amphibious assault. Therefore, U.S. forces could and did sacrifice surprise without endangering any landings.
Landing Craft
Increased production at home and the resultant flow of new types of weapons and equipment overseas did not materially affect the basic pattern of amphibious operations. The debarkation of Marines into landing craft from amphibious transports, the formation of assault
waves, and the trip to the beach itself all remained essentially unchanged. New and improved amphibious vessels and vehicles, however, permitted American forces to conduct landings in a more expeditious manner.
The Fleet Marine Force pioneered in the 1930s the development and testing of landing craft, most notably the shallow-draft Eureka, designed by Andrew J. Higgins, a shipbuilder in New Orleans. Despite the fact that the Navy had developed an experimental type of its own, the Higgins boat “gave the greatest promise, for it could push itself aground on the beach and then retract. In fact this boat was the ancestor of the LCVP (Landing Craft Vehicle and Personnel) that played an important part in the amphibious operations of World War II.”36 Because of its rather fragile hull, however, the Higgins boat could not negotiate the reefs offshore of many of the island targets in the Pacific, whereupon another Marine Corps-sponsored and -developed item, the amphibian tractor, originally conceived for employment in logistical support, was fully utilized as a tactical weapon.
The importance and capabilities of the versatile amtrac as a landing vehicle as well as an assault weapon were fully demonstrated at Tarawa, although they had been employed earlier in the war in the Solomons. On Guadalcanal, the amphibian tractors were used to carry cargo from ship to shore, and once on the island, the artillery employed them in the role of prime movers. “Once in position, however, the gunners found the amphibian was a creature of mixed virtues; tracked vehicles tore up comm wire, creating early the pattern of combat events that became too familiar to plagued wiremen.”37 The amtrac began its career on Guadalcanal in a modest manner, and its “usefulness exceeded all expectations”;38 nobody, however, envisioned using the weird vehicle in much more than a cargo-carrying capacity. After Tarawa, however, “Never again in the Pacific War were assault troops to be handicapped by serious shortages of this vital piece of equipment.”39 Amphibian tractors were later armored and armed with guns, howitzers, and flamethrowers, and utilized to carry the assault wave into the beachhead.
Also making its first appearance in a Central Pacific campaign was the DUKW. Developed for the Army to serve as ship-to-shore cargo and troop transfer vehicles where harbor facilities were inadequate, the value of this amphibian truck was initially exhibited at Kwajalein, where it transported supplies and equipment—mainly artillery and ammunition—to the beaches. When ashore, the DUKWS also supplemented the organic motor transport of the landing
force in support of the operation.40 In all Marine operations in the Pacific after Kwajalein, Army DUKW companies, and Marine DUKW companies in the later stages, were attached to the divisions involved.
British developmental experiments with seagoing landing ships furnished the United States with an insight to solving the problem of getting amphibious forces and all of their combat gear ashore in as complete a package as possible. The most important of the larger landing vessels developed in the war was the LST, which quickly attained a reputation for being “the workhorse of the amphibious fleet.”41
Although hydrographic conditions in the Central Pacific often prevented LSTs from reaching the shore to load or unload their cargoes, these vessels were ideally suited as sea-going transports for DUKWs and amtracs, which could easily offload into the water from the huge LST bow ramp. At the staging area for the Marianas invasions, assault troops and amphibian vehicles were carried to the target on LSTs for the first time in the Central Pacific. This procedure became commonplace in later World War II amphibious assaults in this area.
Depending on how and for what purpose they had been modified, LSTs were employed as offshore radar stations, repair ships, and hospital ships. They were also used as floating platforms from which small spotter planes were launched and recovered by Brodie Gear, which may very roughly be compared to a giant slingshot.
American adoption and further modification of yet another type of landing craft, the LCI, also resulted from earlier British experimentation. Initially employed with ramps on either side of the bow for the rapid offloading of infantry troops at or close to the beach, coral outcropping fringing the island objectives in the Central Pacific prohibited their employment as originally conceived. The LCIs were then converted to gunboats and rocket and mortar boats, and were assigned to the gunfire support group of the amphibious landing force for the purpose of providing close-in fire support of the landing. They first appeared in this role during the invasion of the Treasury Islands.
Both tactical and logistical requirements gave impetus to the development of a family of various types of landing craft and to the modification and improvement of those already in production and service. The considerations of basic amphibious doctrine were constant factors when the configuration and future uses of new types of landing craft were being determined. Fundamentally, these craft had to give the ship-to-shore movement greater power and flexibility and expedite the landing of the supplies
and equipment belonging to and in support of the landing force.
Communications
Other technical innovations, which modified but left unchanged amphibious doctrine and helped to improve the control of ship-to-shore movement and operations ashore, appeared in the field of communications. Improved communications procedure and the development of highly sophisticated radio equipment, which was better suited for employment in amphibious operations than that which had been available at the beginning of the war, soon emerged as a result of the lessons learned in battle.
The most critical period of all in an amphibious assault is immediately before and during the ship-to-shore movement. It is at this time that effective command control over scattered subordinate units is difficult to maintain, especially without an optimum communications performance. Many factors led to a communications breakdown at various times at Tarawa. The interrupted contact between the attack force commander’s flagship and the forces ashore was one that was fraught with the most dangerous consequences. After Tarawa, few such breakdowns recurred because of the introduction into the Pacific of the amphibious force flagship (AGC, which stands for Auxiliary General Communications).
That new type of naval auxiliary ... had been improvised for Admiral Hewitt in the Salerno operation because the network of communications in modern amphibious warfare had become so vast and complicated, and the officers and men necessary to staff amphibious force headquarters so numerous, that no ordinary combatant or auxiliary ship could hold them.42
Along with the improved control of operations overall provided by the equipment and facilities of the AGC was an attempt to ensure that no communications gap would again occur in amphibious assault. To gain this assurance control craft bristling with the most modern communications equipment available were stationed at the line of departure. Not only did these craft organize, control, and shepherd to the beachhead the vessels and amphibious vehicles comprising the initial assault wave, but they also coordinated the landing of subsequent waves.
Technical refinements and modern, up-to-date equipment served together to make an amphibious assault a smoothly functioning and relatively simple type of operation. At the end of the war most if not all kinks had been ironed out. By 1945, testing and practice under combat conditions had given American commanders improved and coordinated supporting arms, close air support, and naval gunfire support systems.
Supporting Arms
Because coordination and control figure so importantly in the conduct of an amphibious operation, every effort was
bent in developing all of the tools and techniques that would make each venture a complete success. Coordination of all three elements of the amphibious force and especially the three supporting arms—air, artillery, and naval gunfire—was vital. The communications failure at Tarawa provided the medium in which the Joint Assault Signal Company was nurtured. The nucleus of Army, Marine, and Navy communications personnel around which the JASCO was formed came from fire support ships, air liaison parties, and shore fire control parties. The JASCO, employed only in the course of amphibious operations, served as a single administrative and housekeeping unit for the naval gunfire teams, air liaison parties, and shore party communication teams required by a division during an assault landing. Just prior to and in the course of operations, all of these teams were parceled out by attachment to the rifle regiments and battalions of the division. The establishment of the JASCOs resulted in a reduction in personnel and operational requirements of their former parent organizations, because the JASCO required fewer skilled communicators who, by employing uniform techniques and radio procedures, reduced the amount of unnecessary traffic and thus unclogged previously overworked radio circuits.
Complementing the JASCOs and also providing an additional measure of coordination and control to the conduct of the amphibious operation were land-based fire support coordination centers (FSCCs), which appeared for the first time in the war at Iwo Jima.43 The establishment of the coordination centers ashore simply was an extension to a point closer to the scene of action of the control exercised aboard the AGC by the task force commander, and permitted a more rapid response to the requests of the infantry unit commanders, although it did not always work out that way. At Okinawa, final authority for the allocation and selection of supporting fires was vested in the artillery representative in the Target Information Center, who generally made his decision in accordance with the advice and recommendations of the representatives of air and naval gunfire.
From the Marine Corps point of view, air support of ground troops by Marine pilots flying Marine aircraft never reached a satisfactory level during the Pacific War. In fact, many World War II Marine aviation commanders considered that their squadrons, groups, and wings were never employed to maximum capability with respect to their tactical functions from a time immediately after Guadalcanal until the Philippines and Okinawa campaigns. In late 1943 and the early months of 1944, tedium and boredom were the order for Marine pilots who, day after day, flew the so-called “Bougainvillea Milk Run,” or bombed and rebombed oft-attacked
atolls and islets that were in the backwash of the war. It may have been good experience for young Marine aviators, but it wasn’t the type of combat for which they had been trained.
The situation improved with the assignment of Marine squadrons to the Philippines and Okinawa operations. Attached to MacArthur’s forces, the Marines amassed an outstanding record of successful and fruitful close air support missions, and proselytized a number of Army commanders who had not previously been aware of the capabilities of this supporting arm. During Okinawa, close air support was flown for the most part by carrier-based Navy flyers, while Marine pilots of TAF flew combat air patrols and provided the air defense of the island. Although these TAF aviators did the most to blunt the Kamikaze threat and downed a creditable if not entirely confirmed number of enemy planes, they still did not fulfill what has come to be recognized as the primary mission of Marine aviation, close air support of Marine ground troops.
The request that Marines support Marines was not based on pride of service alone, as some have suggested—Marine ground commanders were happy to receive air support from any source, provided it came in immediate response to the initial request and did the job for which it had been requested. A less-than-completely satisfactory performance in these two aspects of air support served as the crux of Marine dissatisfaction with the type of support they received until late in the war. This discontent was very strongly voiced in the operations and action reports following the Marianas campaign, where Marine commanders noted that Navy control procedure was relatively inflexible and caused long, needless delays between the request for a mission and its final execution. Another cause for aggravation was that these missions were controlled by naval officers on board ship and out of realistic touch with the situation ashore.
In the Guam campaign, the most critical area of air support operations was communications. Requests for air strikes originated with air liaison parties assigned to each infantry battalion and regiment, and had to be approved up the chain of command and by both division headquarters and the Commander, Support Aircraft, Attack Force. Only one radio circuit, the Support Air Direction net, was made available for these requests, and it was crowded at all times. Additionally, “very few close support strikes were carried out on time or within limits set by requesting agencies” for “the time consumed in request, processing, approval, and final execution was generally 45 minutes to an hour or more.”44 Despite the belief of the Commander, Support Aircraft at Guam that “the time spent [was] justified by the success of the missions, ground units generally asked for more immediate control of planes by air liaison officers and for a method of operations and system of communications that would ensure a faster response to the needs of assault troops.”45
Concluding that air liaison parties should have more direct contact with supporting planes, the Commander, Support Aircraft, Pacific Fleet, backed
the Marines in his comments on air operations in the Marianas.46 He also called attention to the need for greater understanding “on the one hand by the Ground Forces of the capabilities and limitations of aircraft, and on the other hand by the pilots of what they are supposed to accomplish.”47 The problem of control was eased somewhat at Iwo and Okinawa, where Marine LFASCUs and the ALPs were given greater authority and provided a quicker response to the requests of infantry commanders, but full control remained with the command ship-based Navy CASCUs for the greater portion of these two operations.
One Marine demand that was never completely answered was to have Marine squadrons in support of the infantry from the outset of an amphibious assault. At the end of the war, and then too late for their full employment, some Marine escort carriers appeared in the Pacific. Marine close air support techniques and operations never reached full fruition during the war. Not until Korea, where the experience gained in World War II and in postwar landing exercises was tested in the crucible of combat, did Marines fly close support missions for other Marines for any considerable period.
The operations leading to the capture of Tarawa provided the source of many lessons learned, not the least of which was the importance of the role of naval gunfire in an assault on a strongly defended island. Although this should have been apparent, American commanders learned that in order to soften up the target for a landing, the preliminary bombardment had to be heavier and sustained for a longer period than had been the case in previous operations. More importantly, task force commanders learned that:
... the Japanese shore battery could be attacked at short range with reasonable impunity; ships could ‘fight forts,’ at least Japanese forts; and no longer would the concept of gunfire support in the Central Pacific require that ships maneuver at high speeds while firing at long range; indeed the opposite was recommended by Admiral Hill when he suggested that destroyers operate close enough to the beach to use their 40-mm.48
What this meant was that in order to reduce casualties-especially during the assault phase-enemy emplacements would have to be destroyed rather than just neutralized. This concept was a complete reversal of naval gunfire doctrine to that time. Another significant lesson learned about naval gunfire support at Tarawa was “the vital necessity of reducing the time lag between the lifting of fires and the touchdown of the leading wave in order to reduce the opportunity of the defender to recover from the shock of the bombardment. ...”49 All in all, “the lessons of Tarawa showed the ‘doubting Thomas’ that effective gunfire support required a thorough knowledge of the gunnery problem. ...”50 Essentially, in view of the nature
of Japanese island redoubts in the Central Pacific scheduled for future attack, the performance of naval gunfire support had to improve greatly.
One step taken along these lines was the establishment of a shore bombardment training program at Pearl Harbor in September–October 1943. Kahoolawee Island in the Hawaiian group was utilized as a bombardment range at which both fire support ships and their crews and shore fire control parties practiced naval gunfire support techniques that were to prove successful in subsequent operations. According to one observer, the Commander, Cruiser-Destroyer Forces, Pacific Fleet:
... took quite a hard-boiled attitude toward an unsatisfactory performance over this course—and no destroyer went into the forward area without demonstrating proficiency at Kahoolawee.51
Marine commanders never disputed the importance of naval gunfire in support of a landing, and acknowledged its dominant position in comparison with the other supporting arms available to ground forces. “This dominance can be measured by various yardsticks such as weight of fire, rapidity of response, all-weather capability, economy, uninterrupted availability, and peak power during the beach assault itself.”52 Once artillery is ashore, however, it becomes the dominant arm. In general, landing force commanders wanted all of the naval gunfire support they could get; three notable occasions when ground commanders were amply supported were the Marshalls, Guam, and Okinawa.
The amount of naval gunfire available for other operations was limited, however, by certain considerations. For example, during the early stages of the war at Guadalcanal, the threat to the landing by the Japanese fleet forced the U.S. task force commander to reduce the strength of the support force by diverting some ships to stem that threat. At Iwo, a portion of the fleet was assigned to cover the carrier strikes on Tokyo in order to reduce the Kamikaze menace. These, among others, were the reasons given for the fact that the landing forces could not get all of the NGF support that they wanted and needed.
Finally, naval gunfire preparation of an objective prior to a designated D-Day was necessarily limited early in the war in order to maintain the principle of surprise. American naval superiority in the latter stages of the fighting permitted the sacrifice of surprise without endangering an assault landing. It was not only superior strength that allowed tactical and even strategical surprise to be subordinated to ensure the capture of the beachhead. Improvement in the techniques of employment and delivery of naval gunfire did much to guarantee the success of an operation.
Following Tarawa, naval gunfire doctrine was thoroughly reappraised. As pointed out earlier, one conclusion reached was that while area fire could be employed for neutralization in the prelanding period on the morning of a D-Day, it could not effectively destroy enemy gun positions and well-constructed defenses. In order for NGF to
perform its primary task, it was vital that support ships “deliver prolonged deliberate destructive pinpoint fire against known or suspected difficult targets.”53 Accordingly, gunfire support vessels, including battleships, would have to move in close to the beaches. At Kwajalein, NGF was delivered at constantly closing ranges, down to 1,800 yards. Samuel Eliot Morison quotes a conversation that allegedly occurred on the task force flagship bridge after Admiral Turner had given orders for the fire support ships to close the range:
“C.O. of a battleship: ‘I can’t take my ship in that close.’
Turner: ‘What’s your armor for? Get in there!’ ”54
A direct result of the lessons learned at Tarawa was the successful and rapid capture of Kwajalein with significantly smaller losses. Subsequent amphibious operations in the Pacific benefitted similarly. The conduct of amphibious assaults in the period following the Gilberts campaign was so vastly improved and the techniques of amphibious warfare refined to such a degree that, in less than a year after Tarawa was secured, Marines landed on Tinian on 24 July 1944 in what Admiral Spruance considered “was, perhaps, the most brilliantly conceived and executed amphibious operation of the War.”55 General Holland M. Smith, commander of the Expeditionary Troops for both Saipan and Tinian, called the latter one of those “enterprises ... that ... become models of their kind. ... If such a tactical superlative can be used to describe a military maneuver, where the result brilliantly consummated the planning and performance, Tinian was the perfect amphibious operation in the Pacific war.”56
Close on the heels of the end of the Marianas campaign came the bitterly fought battles in the Philippines and on Iwo Jima and Okinawa, The successful amphibious assault at each of these targets was a logical culmination of all lessons learned since Guadalcanal and demonstrated a determination not to repeat earlier mistakes and shortcomings.
Viewing the Pacific War57 Admiral Spruance speculated on three factors that stand out in the development of naval warfare. These were the great growth of carrier strength, the improved ability to make amphibious landings against heavy resistance, and the increased capacity for logistical support of the fleet at ever-increasing distances from Pearl Harbor. One can charge the Marines’ success in the conduct of amphibious warfare to the same three factors. Vital to all this, however, was the development of new techniques and refinement of the old which neither blindly adhered to basic amphibious warfare doctrine nor completely disregarded it either. This thesis best describes the foundations of the strategy leading to victory.
The Japanese
But what of the enemy? In the Pacific, the Allies faced a fantastically implacable, determined, and aggressive foe, who had a strong capability for organizing the ground and constructing defensive works of great strength.
As individual soldiers and small unit fighters, the Japanese were probably unsurpassed in courage and tenacity, but these attributes were not complemented by effective tactical direction. Although the Japanese Army had good field artillery, the support of a flexible artillery organization was lacking. After the loss of Guadalcanal, the Japanese ground troops were denied anything that even resembled effective air support and for all practical purposes, the Japanese were unable to maintain an air offensive that was even worthy of the name. By the end of the Gilberts operation, and certainly by the time that Saipan was invaded, the island outposts defending the Empire had been completely isolated and beyond any hope of reinforcement.
American amphibious assaults in the Central Pacific rapidly took on a pattern which seldom varied throughout the rest of the war. This program was set by the generally small size of the objective combined with the high density and great strength of the defense, particularly at the beachhead. The classic example of this, perhaps, is Peleliu. Once American and Japanese forces were in contact, the determination of the enemy to fight until death and the impregnability of his defenses tended to neutralize the overwhelming fire superiority of the Americans. “This forced our riflemen, with some assistance from combat engineers and tanks to assume the cruelly expensive task of literal extermination of all resistance, long after any hope of vital victory remained to the Japanese.”58 This conclusion is particularly valid in relation to Peleliu, Iwo Jima, and Okinawa, and certainly the latter, where General Ushijima’s Thirty-second Army “extracted the maximum cost for our victory.”59 In an attempt to salvage something in the face of impending defeat, the Japanese finally resorted to the program of Kamikaze attacks in the hope that resulting American losses would force the United States to tire of the war and end it. Although U.S. casualties mounted as a direct result of these attacks, the war effort was not deterred.
The myth of enemy invincibility, and his reputation for cunning and ruthlessness emerged from the record of the Japanese Army in China in the 1930s, the sneak attack on Pearl Harbor, and the relative ease of initial Japanese conquests in Southeast Asia. Marine Corps attitudes towards the enemy were first formed in Shanghai and later tempered in combat at Guadalcanal. The Marine estimate of the opponent basically took two forms. The first was that the Japanese could be defeated by employing their own tactics against them, and by becoming as adept as the enemy in jungle warfare. The Marines were not novices in fighting in the tropics, for many of the regulars had received their baptism of fire in the Banana Wars. The second attitude, one of deep mistrust, was
based on a number of incidents which had occurred in the early days of the war in the Philippines and at Guadalcanal.
One specific episode at the root of this mistrust which strongly affected the Marine temper when it became known was the unfortunate Goettge Patrol on Guadalcanal.60 As soon as the particulars of what had happened to the patrol reached the rest of the division:–
... hatred for the Japanese seared the heart of the Marine Corps. This episode ... followed by devious trickery, such as playing dead before tossing a grenade, made it difficult to indoctrinate Marines on Guadalcanal and later with the necessity of taking prisoners of war for the purpose of gaining information. Such an attitude, combined with the adamant refusal of most Japanese to surrender under any circumstances, hobbled intelligence work in the field.61
Repercussions stemming from the knowledge of this event continued as long as the Pacific War lasted.
With each succeeding Pacific amphibious assault, more chinks and defects in the Japanese military system were exposed and exploited. The step-by-step process by which the enemy was defeated cost the Americans dearly, but in the end, Japanese attrition was the heavier. Perhaps no fighting men in the war suffered so much as those who comprised the pitiful remnants of the once-proud Japanese units that retreated from Guadalcanal, those that withdrew from Cape Gloucester to Rabaul, and others that withered on the vine on the bypassed islands of the Pacific. Once Japanese fortunes waned and the American offensive began to roll, these forces were neither reinforced, replenished, nor succored. Collectively, they were indeed a forlorn hope in the most descriptive sense of this term.
Other factors in addition to the effective application of the doctrine of amphibious warfare and subsequent refinements strongly influenced the Marine Corps role in the Pacific War. Such considerations as the strength and organization of Marine divisions and aircraft wings, combat developments and tactical innovations, and improved and new weaponry together provided the bases leading to a successful conclusion of each campaign to which Marine Corps units were committed.