Initially trained in gunnery, Yamamoto became a leading advocate of naval airpower during the 1920s and 1930s, in part because of his experiences as chief executive officer at Kasumigaura Naval Flight School between 1924 and 1926, when he became a pilot as well. Also significant in forming Yamamoto's perceptions were his two periods as a resident officer in the United States. Between 1919 and 1921, he studied English at Harvard University. Promoted to captain in 1923, he served as naval attaché in Washington, D.C., from 1926 to 1928. Yamamoto's time in the United States persuaded him of that country's unlimited economic potential and the relatively low quality of the U.S. Navy.
On returning to Japan from the United States, Yamamoto took command of the aircraft carrier Akagi and used her as a platform to test out new concepts in naval aviation. He was a delegate to the 1929–1930 London Naval Conference. He became chief of the navy's technical service in 1930 and was promoted to rear admiral the next year. In this position, he pushed the development of modern aircraft for the navy. In 1933, he took command of the 1st Naval Air Division. Yamamoto headed the Japanese delegation to the 1935–1936 London Naval Conference, where he presented Tokyo's position that it would no longer abide by the 5-to-5-to-3 naval ratio with the United States and Britain. He returned home a hero. Appointed vice minister of the navy in 1936, Yamamoto opposed his government's decision to proceed with construction of the giant Yamato-class battleships, believing they were a waste of precious resources. Unable to overcome the reliance on traditional battleships, Yamamoto nonetheless pushed the construction of aircraft carriers, long-range bombers and flying boats, and the new Zero fighter. His opposition to the increasingly belligerent official position led to his removal from his government post.
Appointed commander in chief of the Combined Fleet in August 1939 and promoted to full admiral in November 1940, Yamamoto opposed Japan's adherence to the Tripartite Pact and the movement toward war with the United States. Although he allegedly remarked privately that he would "run wild" for six months to a year, he had "utterly no confidence" after that. Nonetheless, he rejected the navy's original plan to lie in wait for the U.S. Pacific Fleet in the Far East, after the American ships had been savaged by submarine and torpedo attacks. Instead, Yamamoto devised a preemptive strike against the Pacific Fleet anchorage at Pearl Harbor in the Hawaiian Islands. He hoped that by crippling U.S. naval power at the war's outset, Japan might use the breathing spell that would ensue to conquer the Southern Resource Area and erect an impregnable defensive barrier.
Yamamoto did what he could to prepare his fleet for war, purging ineffective officers and insisting on realistic, rigorous—even dangerous—training, both day and night, so that when war came, the fleet was the best trained in the world, certainly at night fighting. However, he ignored technological advances, such as radar, which Japanese ships did not receive until 1943.
The success of the Pearl Harbor attack on 7 December 1941 enhanced Yamamoto's prestige, which he used to persuade the Naval General Staff to accept his overly complex Midway plan in April 1942. Designed to draw out the remnants of the U.S. Fleet, specifically the carriers absent from Pearl Harbor on 7 December, Yamamoto's Midway campaign ended in disaster on 4–6 June with the Combined Fleet's loss of four fleet carriers, a blow from which the Japanese navy never recovered.
Although the tide of the Pacific war clearly shifted in favor of the Allies after Midway, U.S. leaders remained wary of Yamamoto's leadership. Accordingly, when U.S. intelligence learned that Yamamoto intended a one-day inspection trip to the northern Solomons in April 1943, the Pacific Fleet commander, Admiral Chester Nimitz, with the approval of President Franklin D. Roosevelt, dispatched aircraft to intercept his plane. On 18 April, P-38 fighters shot down Yamamoto's aircraft near Buin in southern Bougainville Island, killing the admiral. His remains were recovered and returned to Tokyo, where he was honored with a state funeral.
Bruce J. DeHart and Spencer C. Tucker
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