Yamamoto and Risk at Midway(Davis)

NW3230: Ian Davis-Yamamoto’s Risk at Midway

Yamamoto risked his fleet at Midway in June 1942. Evaluate how Yamamoto

addressed the operational and strategic risks. Did Yamamoto risk too much or too little?

And did the risks outweigh the rewards?

Introduction

Admiral Yamamoto of the Japanese Imperial Navy risked too much with his plan

to seize Midway in June of 1942, an objective that was insignificant to Japan’s overall

war plan. Strategically, he sought to lure the United States Navy to commit their carriers

to a decisive engagement in the intent that the Japanese forces would destroy them.

Operationally, Yamamoto determined that the seizure of Midway would be the catalytic

event to provoke a U.S. response and the commitment of the carriers to protect the

Hawaiian Islands from Japanese expansion. He assessed that the destruction of the U.S.

carriers and the seizure of Midway would be the springboard to secure Hawaii and

eventually harass the Pacific Coast of the United States, even though this did not nest into

Japan’s strategic plan. In his effort to stop U.S. power projection in the Western Pacific,

Yamamoto risked not only critically short carrier-based airpower to conduct unnecessary

offensive operations, but also risked the collapse of the already strained Japanese

defensive perimeter. Yamamoto and his staff irrationally “assumed away” strategic and

operational risk in order to achieve an unnecessary objective.

Strategic Risk in the Pacific

Aircraft carrier-delivered naval airpower served as formidable tool for strategic

power projection and strategic centers of gravity for both Japanese and American naval

operations in the Pacific during World War II. The strategic objectives of the Japanese

Empire were focuses on obtaining vital natural resources to sustain its wartime industrial

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base that was depleted from decades of conflict with regional enemies. The political-

economic conditions imposed by the entente of America, Britain, China, set the

conditions for Japanese expansion in the Pacific for economic independence, political

autonomy, and to assert Japan’s divine destiny. Anticipating the impending increase of

U.S. combat power in the Pacific, Admiral Yamamoto developed a decisive strategic plan

to annihilate the U.S. Pacific fleet anchored at Pearl Harbor with a surprise carrier-based

air strike. Although the Japanese surprise attack on Pearl Harbor dealt a devastating blow

to the Pacific fleet, it failed to achieve all of its planned objectives, including the strategic

objective of crushing the American will wage war with Japan. Failing to destroy the U.S.

carriers during the Japanese attack of Pearl Harbor on December 7, 1941, Admiral

Yamamoto determined that the strategic priority was the elimination of the elusive

American’s carrier fleet in order to secure the Imperial defensive perimeter and occupied

territories, protect the Japanese home island, and to set conditions for further Japanese

expansion. (Baer, 1994, pp. 164-180) The destruction of the American carriers, and the

subsequent occupation of American territory, became an obsessive, irrational priority that

drove Admiral Yamamoto to risk the overall success of Japan’s war in the Pacific.

To achieve these strategic objectives, Yamamoto was willing to risk critical

national assets on unnecessary operations that were not nested in the plans of the

Japanese Imperial General Headquarters. From inception, operations in the Central

Pacific and the Eastern Operation to invade Hawaii were considered frivolous and a drain

on Japan’s already depleted resources. From the Japanese Army’s standpoint, combat

operations in Manchuria, China, Burma, and occupied territories in the South Pacific had

its troops stretched to their limits. The rapid sequence of Imperial military victories after

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December of 1941 expanded Japan’s footprint to point that was logistically cumbersome

and lacked the required combat power for proper defense. Land-based airpower was

critical to enabling the Imperial victories and the defense of the Japanese occupied

territories and synergistically increased the effectiveness of Japanese carrier-centric

offensive and defensive operations. Assuming that America and its allies would use the

Sea Lines of Communication (SLOCs) to Australia in order to project combat power into

the region for an eventual push to recapture the Philippines and pressure the Japanese

main islands, Yamamoto advocated taking an offensive, rather than defensive, posture.

He envisioned the expansion of the Japanese by establishing footholds in the Aleutian

Islands (Operation AL), Midway and the Hawaiian Islands (Operations MI), while

Japanese defensive forces secured the South Pacific perimeter. Instead setting the

conditions to lure the American Pacific Fleet into decisive battle to interdict the

Australian lines of communication with mutually supporting Japanese air, land, and sea

power defenses (a mobile defense), the Imperial General Headquarters endorsed

Yamamoto’s plan to conduct a strategic offensive operation hinged on supporting

operational plans that were not nested in the Japan’s overall strategic plan. Furthermore,

the operational plans were not mutually supporting, and were not properly resourced to

achieve their objectives. (Parshall & Tully, 2005, pp. 19-38)

The cumulative strategic effects of Yamamoto’s erroneous risk assessment risked

the destruction of the Japanese carrier-based airpower and Combined Fleet forces

conducting offensive operations, a collapse of the Japanese Pacific defensive perimeter

and secured territories, the loss of critical resources, and set the conditions for the Allies

to secure a foothold in the Southwest Pacific for a push towards Japan. (Wylie, 1989)

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Additionally, the “Imperial Navy Operational Plans for Stage Two of the Great East Asia

War” was not supported by the majority of the Japanese command and hinged on false

assumptions about the Allied will and capacity to oppose the Japanese Imperial forces’

expansion East of the International Date Line. (Parshall & Tully, 2005, p. 33-38) Driven

by a myriad of cultural, organizational, doctrinal, and personal issues, Admiral

Yamamoto’s strategic offensive plan risked too much on unnecissary objectives that were

insignifigant to achieving Japan’s strategic objectives. (Parshall & Tully, 2005, pp. 19-

114, 397-414)

Operational Risk at Midway

The primary operational objective of Admiral Yamamoto’s Central Pacific

Operation was the destruction of the American Fleet and their key source of combat

power, the aircraft carriers. To achieve this objective, Admiral Yamamoto intended

venture beyond the range of Japanese land-based airpower provided by the Japanese

defensive perimeter and seize key American terrain to entice the Pacific Fleet to commit

their carriers to the battle. Once located, the Imperial Japanese Navy could use its

carrier-based airpower to destroy the American carriers, thus providing uninhibited

freedom of movement for Japanese forces in the Pacific. Yamamoto and the Imperial

Command assessed that without the ability to project power in the in the Pacific, the

American fleet would not have the ability to disrupt Japanese operations and

subsequently could buy time and space militarily for Japan. Operation MI would serve as

bait to lure American carriers into a decisive engagement and set conditions for future

operations in the Hawaiian Islands. (Murray & Millet, 2000, pp. 169-195) Lacking

accurate intelligence and falsly assuming that the America and its allies lacked the

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military or psychological capability to defeat superior Japanese war machine, Japan

unnecissarily committed critical assets to operational objectives without appropriately

determining or mitigating risk.

The successful attack of Tokyo, Japan on April 18, 1942 by a force of twelve

carrier-launched American B-25 bombers led by Lieutenant Colonel James H. Doolittle

codified Yamamoto’s argument of the imperative to actively find and destroy the

American naval airpower in the Pacific and that attacks on the Japanese main islands

were inevitable if action was not taken immediately. (Murray & Millet, 2000, pp. 190-

192) After the Doolitlle raid, the Imperial Japanese Navy assessed that the American

naval carrier force consisted of the Lexington, the Yorktown, the Enterprise, the Hornet,

and potentially the Wasp. At the battle of the Coral Sea, the Japanese assessed that they

sunk the American carriers Lexington and the Yorktown, but in reality the Yorktown was

damaged and would make its appearance again at Midway. Coral Sea also took a toll on

the Japanese carriers Shoho and Zuikaku, leaving them combat ineffective and not

availaible as part of the planned Operation MI force package. Despite these losses,

Admiral Yamamoto assumed that he had enough assets to suceed with his Midway plan

based on the possible American forces availble in theater and the superior Japanese

military might.

Leveraging surprise and deception, the Imperial Navy intended to present the

picture that a small Japanese force intent on siezing Midway and trigger the commitment

of the U.S. carriers. Meanwhile, Yamamoto’s larger main effort would be out of the

range of U.S. scout planes and poised to fix and destroy the Pacific Fleet in the

engagement area before they realized the true asymmetry of relative combat power and

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withraw. Furthermore, Midway was determined to be vital and proximate enough to

trigger a U.S. response, but far enough away from Oahu to be supported by land-based

airpower. Key to the success of the operations a Midway was the establishment of

forward refuling sites at French Frigate Shoals to support seaplane scouting operations of

Operation K gather intelligence on the American Fleet.

Unknown to Admiral Yamamoto, his operational surprise was lost with the

cracking of the Japanese JN-25 radio code by American cryptographers that knew of the

impending attack and postured forces to counter the Japanese assault. Despite indicators

of signifigant increased American activity in the area and the cancellation of Operation K

due to the presence of American forces at French Friggate Shoals, Admiral Yamamoto

pressed on with his original plan without regard to a change in the operational situation

and unnecessarily exposed the entire Operation MI mission and force to catastrophic risk.

(Parshall & Tully, 2005, pp. 92-105)

The Japanese Navy’s irrational decision to continue with its scripted Midway

invasion plan despite being under resourced to overcome the presence of increased

American combat power was too risky in the face of the new operational picture. The

risky gamble cost Japan the aircraft carriers Akagi, Kaga, Soryu, and Hiryu, the success

of Operation MI, and essentially opened the door for the eventual American push towards

the Philippines. Admiral Yamamoto’s obsession with the offense led to the failure of

Japanese operational and strategic objectives.

Not Enough Risk

Some may argue that Yamamoto risked too little to destroy the U.S. carriers in the

Pacific and establish a foothold for the Eastern Pacific Operation. The American

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bombing attack of the Tokyo and growing strength of the Allied forces in the theater

posed a serious risk to the Japanese defensive perimeter and the critical natural resources

that Japan needed to continue its war effort. The Hawaiian Islands were an American

center of gravity for the war in the Pacific and were critical for power projection and

logistics. Arguably, if Japan would have re-sequenced and committed more assets to

Operations MI and AL, then Admiral Yamamoto could have not only seized Midway, but

continue the push to Oahu without opposition from the deadly American carrier-based

airpower. Furthermore, the loss of the U.S. forward base at Pearl Harbor would have cut

the SLOCs to Australia and set the conditions for the expansion of the Japanese defensive

perimeter southward, thus gaining access to more natural resources. Essentially, greater

strategic and operational risk would have yielded greater strategic and operational

success for Japan.

While more risk may have yielded more gains, the ground truth was the

cumulative effects of Japan’s protracted war, the sheer enormity of the Japanese

defensive perimeter, political rivalry and infighting, no unity of effort, a depleted fighting

force, and an exhausted military industrial base, Admiral Yamamoto did not have any

more assets available to risk without diverting assets from Operation AI. While this

would have provided additional combat power at Midway, the lack of intelligence on the

disposition of American carriers and activities in Hawaii essentially would have exposed

more Japanese assets for destruction in the American engagement areas. The Imperial

Navy’s rigid adherence to the scripted battle plan, lack of operational flexibility, and

blatant disregard of indicators that the Operation MI attack plan was compromised would

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have led to the destruction of the combined MI/AL fleet. In the case of the battle of

Midway, more risk would not have yielded greater rewards.

Conclusion

Admiral Yamamoto’s obsession with the offense and faulty assessment of

strategic and operational risk drove a plan for destroying American aircraft carriers in the

Pacific and seizing Midway Island that was unnecessary and irrational. Based on his

erroneous risk analysis, he committed Japanese forces to an engagement that was

destined for failure and not vital to Japan’s national interests. The defensive posture of

the Japanese perimeter, with it’s capability to provide mutually supporting land-based air

power, was the stronger strategy and would have brought more combat power to bear on

Allied expeditionary forces in the Pacific. Anticipating the Allied drive towards

Australia to eventually try to recapture the Philippines, Yamamoto could have still lured

the U.S. carriers into a decisive engagement area that had the support of land-based

airpower from the mobile defense. This would have nested into Japan’s overall strategic

objectives and bought time and space for the Japanese forces to refit and prepare to meet

the advancing Allied forces from a position of strength without unnecessary risk. In the

end, Admiral Yamamoto’s same audacious leadership that delivered a crushing blow to

the Pacific Fleet at Pearl Harbor, caused the Japanese Imperial Command to risk critical

wartime assets on and irrelevant objective that signaled a turning point of the war in the

Pacific.

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Bibliography

Baer, G. W. (1994). One Hundred Years of Sea Power: The U.S. Navy, 1890-1990. Stanford, California: Stanford University Press.

Murray, W., & Millet, A. T. (2000). A War to be Won: Fighting the Second World War. Cambridge, Massachusetts: Harvard University Press.

Parshall, J. B., & Tully, A. B. (2005). Shattered Sword: The Untold Story of Midway. Washington, District of Colombia: Potomac Books.

Wylie, J. C. (1989). Appendix A: Excerpt from 'Reflections on the War in the Pacific'. In U. S. Institute, Military Strategy: A General Theory of Power Control (pp. 117-121). Annapolis: Naval Institute Press.

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Yamamoto and Risk at Midway(Davis)

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