SAMS Monograph Body

MAJ Merbin Carattini

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Evolution of Operational Art 31 October 2012 Joint Operations in the Philippines (WWII)

Operational Approach

General Douglas MacArthur's return to the Philippines began on the Island of Leyte in

October 1944. The battle of Leyte Gulf in October saw most of the Japanese surface fleet destroyed with little to show for its sacrifice. Yet, the primary objective of assaulting Leyte was to provide a staging area for a much larger effort, the assault against the Island of Luzon where most of the Japanese land defenses lay. For this effort, MacArthur developed an operational approach based on two axes of advance to defeat the Japanese in the Philippines. These axes of advance were developed to establish bases of supply, sustainment, and support within range of the Japanese homeland. MacArthur’s Southwest Pacific Area had given up the north coast of

New Guinea to Morotai Island to advance towards Luzon and gain the initiative towards an attack against Japan1 (See Figure 1).

MacArthur divided operations into three phases utilizing a decisive, shaping and sustaining operational framework to direct Allied Land Forces to seize and secure a beachhead on

Lingayen Gulf on Luzon after Leyte Island was captured. During the first phase, MacArthur planned to set the conditions to bypass Mindanao and set up operations in the Island of Leyte for

1 Andrade Dale, “The Campaigns of World War II: Center of Military History – Luzon”. United States Center of Military History (October 2003), http://www.history.army.mil/Luzon.72-78.html (accessed October 2012).

1 MAJ Merbin Carattini

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Evolution of Operational Art 31 October 2012 an assault at the Gulf of Lingayen at Luzon. Throughout this phase, Allied Air Forces and Allied

Naval Forces would establish air and naval superiority to allow uninterrupted flow of troops towards Leyte, and Luzon thereafter. Once air and naval superiority was established, a base of air operations at Mindoro provided the best reach for Air support during the occupation of Luzon.

The last phase of this operation was an amphibious assault in the Gulf of Lingayen ensuring that

Allied Land Forces occupy the Central Plains towards Manila and Manila Bay. The movement of

Allied Forces from Lingayen Gulf towards Manila Bay would establish a foothold in the

Philippines Archipelago to attack Japan and liberate Filipinos from Japanese forces.

Based on the strategic context, McArthur had two problems to solve with limited resources. First, how to secure a supply base within range of Japan and second, how to seize

Luzon for power projection in order to enable Philippines sovereignty and set the conditions for attacks into Japan homeland. McArthur had two amphibious fleets, three air force elements, and two armies as land component for the operation. The Japanese forces operating in Luzon totaled approximate 200,000 troops. He had factors to consider such as weather, Chinese allies defeated in the Indo-China sector, kamikazes, a balance between offensive momentum and logistical constraints, and allied prestige of liberating a former United States colony.

Decisive Operation

The decisive operation was assigned to the 6th Army under the command of Lieutenant

General Walter Krueger for the seizure of Luzon, specifically Manila Bay and the central plains, to establish air, naval, and a land base supply for future offensive projection against Japan. The

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Evolution of Operational Art 31 October 2012 task was to establish a beachhead on the Gulf of Lingayen against possible determined opposition that would allow continual inflow of forces, and drive south through the Central Plains towards

Manila and Manila Bay.

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Evolution of Operational Art 31 October 2012

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Evolution of Operational Art 31 October 2012 Figure 1 – Map of Philippines

Shaping Operations

The shaping operations included air support by the 14th and 21st air force, naval support by the 3rd and 7th Fleet in the South China Sea, Leyte, and Mindoro attacks to secure air bases.

From the Allied Air Forces, their principal mission was to establish air and naval superiority to deny Japanese reinforcement through the Lingayen Gulf.2 They would also strike the southern portion of Luzon before the beach assault and amphibious operations in the Lingayen Gulf, creating a deception mechanism forcing the Japanese to move away from the Allied Land Forces’ northern avenue of approach. In addition, the Allied Naval Forces were to transport land-based forces from 6th Army to the Lingayen Gulf, while protecting the assault convoys via indirect fire, mine sweeping operations, and preliminary bombardment prior to the occupation of Luzon.

Moreover, Allied Naval Forces had to prepare for potential Japanese naval engagements in the

South China Sea.

Sustaining Operations

The sustaining operation supported by Army Services and naval logistical elements provided decentralized systems that allowed initial flexibility throughout the Philippine

Campaign. Once established at Luzon, the Services and Supplies Department would centralize

2 Smith, Robert Ross and Center of Military History. 1991. Triumph in the Philippines. Washington, D.C.: Center of Military History, U.S. Army, 35.

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Evolution of Operational Art 31 October 2012 the supply system that ensured an open flow of logistics to support the fight.

Background and Strategic Context

During the spring of 1944, senior United States politicians and military leaders questioned the merits of seizing Luzon over the Chinese island of Formosa, as the point or hub for direct operations against Japan. Admiral Ernest J. King, the Chief of Naval Operations, had long objected to landings in the Philippines, and by May 1944, Army Chief of Staff General

George C. Marshall and Army Air Force Chief of Staff General Henry H. Arnold joined him.3

Marshall felt that MacArthur's Luzon plan would be "the slow way" and that it made more sense to "cut across" from the Mariana Islands to Formosa. MacArthur, on the other hand, argued that the Formosa route was militarily "unsound" and that the Philippine Islands provided a more sensible staging area for the final assault against the Japanese islands.4 As commander of the

Philippine defenses in 1941 during Japanese offense, MacArthur felt a strong moral responsibility to free the islands of the brutal Japanese occupation. Therefore, he made the Philippines a major objective for his Southwest Pacific Asia Command.

By July 1944, most planners agreed that an invasion of Formosa was not logistically feasible in the near future. In September, the Joint Chiefs approved a December starting date for

3 Andrade Dale, “The Campaigns of World War II: Center of Military History – Luzon”. United States Center of Military History (October 2003), http://www.history.army.mil/Luzon.72-78.html (accessed October 2012).

4 Ibid.

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Evolution of Operational Art 31 October 2012 the United States’ invasion of Leyte Island in the central Philippines.5 Once established in Leyte

Island, this force would assault in Luzon, which is the largest, northernmost of the Philippine islands.

From the Japanese perspective, maintaining control and access to the islands was vital.

Loss of the Philippines would threaten Japan's access to oil and critical raw materials from abroad, specifically from the East Indies and Southeast Asia. For this reason, Tokyo's naval and army leaders made the defense of the Philippines their major war effort in 1944.6 Japan selected as the land forces in the Philippines, General Tomoyuki Yamashita who was a successful conqueror of British Malaya and Singapore. He had an estimate of 430,000 troops stationed all across the islands. Moreover, the Japanese naval leaders were also prepared to commit the entire battle fleet on behalf of the Emperor in the Philippine Islands.7

Tenets of Unified Land Operations

The tenets of unified land operations describe the Army’s approach to generating and applying combat power in campaigns and major operations.8 To analyze further the arrangement

5 Ibid.

7 Ibid, 19.

8 Department of the Army. Unified Land Operations. Army Doctrine Publication (ADP) 3-0, (Washington DC: The Pentagon, October 2011), 7.

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Evolution of Operational Art 31 October 2012 of tactical actions during this campaign, the tenets of unified land operations provide a comprehensive view of the relationships among the capabilities used during the Philippines

Campaign. These tenets include: flexibility, integration, lethality, adaptability, depth, and synchronization.

Flexibility

Flexible plans help units adapt quickly to changing circumstances in operations.

Commanders create opportunities for initiative by anticipating events that allow them to operate inside of the enemy’s decision cycle or react promptly to deteriorating situations.9 MacArthur eliminated the first-phase operations when, in mid September 1944, the changing situation in the western Pacific made it possible for him to move directly to Leyte, thus bypassing Mindanao.10

His ability to remain flexible to an ever-changing situation allowed Allied Forces to gain the necessary speed to strike Japanese forces and achieve initiative in establishing a foothold in

Luzon.

Integration

Military forces do not operate independently, but as a part of a larger unified action.

Leaders integrate joint operations within this larger effort to achieve unity of effort. Through the

9 Ibid, 7.

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Evolution of Operational Art 31 October 2012 mission command warfighting function, commanders, assisted by their staffs, integrate numerous processes and activities within the headquarters and across the force. Commanders extend the depth of operations through joint integration.11 During this campaign, MacArthur was able to integrate naval, air, and land forces into a common goal to achieve success. The arrangement of tactical actions of all joint capabilities, to include naval, air, and land, enabled MacArthur to extend his operational reach despite a constraint logistical environment. Integrated naval fire support, air superiority, and land forces became the most important consideration during this campaign.

Lethality

The capacity for physical destruction is a foundation of all other military capabilities, the most basic building block for military operations. Lethality is a persistent requirement for Army organizations, even in conditions where only the implicit threat of violence suffices to accomplish the mission through nonlethal engagements and activities.12 MacArthur was able to increase his forces’ lethality because he was able to concentrate firepower at the enemy’s weaknesses forcing them to withdraw to the mountains.

Adaptability

11 Department of the Army. Unified Land Operations. Army Doctrine Publication (ADP) 3-0, (Washington DC: The Pentagon, October 2011), 8.

12 Ibid, 8.

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Evolution of Operational Art 31 October 2012 Adaptability is essential to seizing, retaining, and exploiting the initiative based on relevant understanding of the specific situation. For example, leaders demonstrate adaptability while adjusting the balance of lethal and nonlethal actions necessary to achieve a position of relative advantage and set conditions for conflict resolution within their areas of operations.13

MacArthur’s anticipation of transitions between operations demonstrated his adaptability to changes in the operational environment. He accepted risks that allowed Allied Forces to create opportunities to increase the probability of their success. For example, his judgments about intelligence estimates based on experience, decision to bypass Mindanao and go straight for

Luzon via Mindoro, and deception operations south of Luzon, allowed United States forces to adapt quickly to changes in Japanese forces’ reactions.

Depth is the extension of operations in time, space, or purpose, including deep-close- security operations, to achieve definitive results. Army leaders strike enemy forces throughout their depth, preventing the effective employment of their reserves, command and control nodes, logistics, and other capabilities not in direct contact with friendly forces.14 By attacking the

Japanese forces in depth across the spectrum of their capabilities, to include Japan’s air force and navy, MacArthur not only integrated the Allied Forces team but also extended the operational reach denying Japan to reinforce.

13 Ibid, 8.

14 Ibid, 8.

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Evolution of Operational Art 31 October 2012 Synchronization

Synchronization is the arrangement of military actions in time, space, and purpose to produce maximum relative combat power at a decisive place and time (JP 2-0). It is the ability to execute multiple related and mutually supporting tasks in different locations at the same time, producing greater effects than executing each in isolation.15 This campaign shows one of the best examples of synchronization of capabilities despite not being a unified command structure. The issues that surfaced in lieu of original naval plans conflicting with MacArthur’s plan created a situation that could have turned difficult to achieve synchronization. However, common understanding and successful arrangement of tactical actions surpassed personality differences and achieved synchronization.

Conclusion

For the first time during the Pacific theater of WWII, American forces deployed a field army making for a sometimes-unwieldy command structure. In earlier campaigns throughout the

Pacific, the U.S. theater commanders had generally employed one or two divisions at a time to seize small islands or small portions of coastline. In contrast, the Luzon Campaign saw extended operations inland which demanded the deployment of multi-corps forces supported by an increasingly expanded logistical and communications systems. Fortunately for the Americans, all but one of the participating U.S. divisions had previous experience in fighting the Japanese,

15 Ibid, 9.

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Evolution of Operational Art 31 October 2012 particularly on Leyte, only a few months before. In fact, except for the urban fighting in Manila,

American units were in the enviable position of applying past lessons to the battlefield.

The Americans also had the advantage of superior weapons, equipment, and supplies. Therefore,

American forces controlled both the local seas and air by January 1945. Finally, the flat open plains of central Luzon were conducive to the Americans' advantage in maneuverability and firepower. During earlier battles on the Pacific's small jungle islands, the terrain often worked to the Japanese’s advantage; however, on Luzon, the reverse was so. If American soldiers needed any other impetus, many of them received it when they saw the horror of Japanese prison camps.

To many, it made the difficult battle of Luzon a possible invasion of the Japanese mainland seems worthwhile, which was the strategic purpose for the occupation of Luzon.

Bibliography

Dale Andrade, “The Campaigns of World War II: Center of Military History – Luzon”. United States Center of Military History (October 2003), http://www.history.army.mil/Luzon.72-78.html (accessed October 2012).

Department of the Army. Unified Land Operations. Army Doctrine Publication (ADP) 3-0, (Washington DC: The Pentagon, October 2011).

Smith, Robert Ross and Center of Military History. 1991. Triumph in the Philippines. Washington, D.C.: Center of Military History, U.S. Army.

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Evolution of Operational Art 31 October 2012