World War II Day by Day

Tokyo, Japan • November 11, 1940

Seventh child to a Japanese schoolmaster and his second wife and named “Iso­ruku” to memo­ri­alize his father’s age (56), the future com­man­der of the Impe­rial Japa­nese Navy’s Com­bined Fleet (Rengō Kantai) for much of World War II would seem to have been born under, what West­erners might call, a lucky star. From the time he served as naval attaché at Tokyo’s embassy in Washing­ton, D.C. (1925 to 1927) and even before as a stu­dent at Har­vard Uni­ver­sity in Boston, Massa­chus­etts (1919 to 1921), until his vio­lent death at age 59 on April 18, 1943, by a venge­ful United States, Adm. Iso­ro­ku Yama­moto appears to have weathered World War II histo­ri­og­ra­phical mael­stroms better than most of his compatriots of the period.

Yamamoto’s first major assignment was exe­cu­tive offi­cer at a recently opened naval air-training school north of Tokyo. From that point on in his naval career Yama­moto pressed for the develop­ment of air­craft, fighters and torpe­do planes espe­cially. He and U.S. Army Gen. William “Billy” Mit­chell shared similar view­points about air power. “The day has passed,” Mit­chell proph­e­sied in late 1918, “when armies on the ground or navies on the sea can be the arbiter of a nation’s destiny in war. The main power of defense and the power of ini­ti­a­tive against an enemy has passed to the air.” One pro­duct of Yama­moto’s pres­sure was the famed Mit­su­bishi Zero fighter plane of World War II. Another was pushing the navy to build more air­craft carriers, which in time led to the Sho­kaku and Zui­kaku, the biggest and fastest carriers Japan had yet built.

Yamamoto had frequent praise and respect for Amer­ica and Amer­i­cans. Following his country’s sur­prise attack on U.S. Pacific assets in Hawaii on Decem­ber 7, 1941, he became America’s favor­ite villain over­night. After all, Yama­moto was the chief archi­tect of that infa­mous attack. Yet in 1934, opposing Gen. Mit­chell’s stance on the inev­i­ta­bility of war with Japan, Vice Adm. Yama­moto said, “I have never thought of America as a poten­tial enemy, and the naval plans of Japan have never included the possi­bil­ity of an Ameri­can-Japa­nese war.” In the late 1930s/turn of the ’40s Yama­moto was a leading propo­nent of avoiding war with the United States. He and many higher-ups in the Japanese Navy saw eye to eye in believing their navy was too weak to oppose the U.S. Navy and would remain so for some time. But Japan’s govern­ment came under irrepres­si­ble pres­sure from the Japa­nese Army, chiefly from the coun­try’s Minis­ter of War (July 22, 1940, to July 22, 1944) and future prime minis­ter (Octo­ber 18, 1941, to July 22, 1944), Gen. Hideki Tōjō, and Gen. Tōjō set a collision course with America.

As head of the Combined Fleet Yama­moto realized that if his coun­try was facing an inev­i­ta­ble con­flict with a power­ful adver­sary like the U.S., he was duty-bound to give Japan a fighting chance. So, in late spring 1940 he began mulling over ways to cripple the U.S. fleet at anchor in Pearl Harbor in the mid-Pacific in the opening hours of the war. Months later, on this date, Novem­ber 11, 1940, two flocks of British bi­planes armed with torpe­does lifted off the carrier HMS Illus­tri­ous in the Medi­ter­ranean Sea to launch the first all-aircraft, ship-to-ship naval attack in his­tory, blud­geoning Italy’s Regia Marina at Taranto for the loss of 2 air­craft, 2 killed, and 2 captured. Yama­moto dis­patched two assis­tant naval attachés to Taranto to inves­ti­gate and report back on the carrier air strike firsthand.

Early in 1941 Yamamoto outlined an attack plan simi­lar to the Royal Navy’s air attack on Taranto. In April 1941 he ordered plans drawn up for Oper­a­tion Z, a dicey pre­emp­tive air and naval attack on Pearl Harbor, con­fiding to a staff offi­cer, “If we fail, we’d better give up the war.” Far from failing, Yama­moto’s strike removed 88 per­cent of the U.S. Pacific Fleet’s battle­ships (or 60 per­cent of the U.S. Navy’s capi­tal ships) from com­bat ser­vice in less than 3 hours at little cost. The war between Japan and the United States and its allies would last for 1,365 days.

Japanese Attack on Pearl Harbor, December 7, 1941

Left: A sketch identifying ship mooring locations and titled (at upper left) “Report on posi­tions of enemy fleet at anchor­age” after it was recovered from a Japa­nese air­craft that was downed during the attack on Pearl Harbor. Oper­a­tion Z had a Hawai­ian spy net­work com­po­nent, half of which con­sisted of a young 28-year-old, real name Takeo Yoshikawa, whose cover was that of Japa­nese vice con­sul offi­cer trainee Mori­mura Tadachi working in the office of con­sul gene­ral Kita Nagao, who him­self was a secret agent of the Joho Kyoku, the intel­li­gence ser­vice of the Impe­rial Japa­nese Navy. Yoshi­kawa was assisted by a two-person team of Joho Kyoku agents, plus local fisher­men, painters, and simple tou­rists. The other half con­sisted of the Kuehns, a Nazi hus­band-and-wife team working in the pay of both Ger­many and Japan. The Kuehns rented a cot­tage over­looking Pearl Harbor. The spy net­work pro­vided infor­ma­tion leading to the suc­cess of Japan’s sur­prise attack; for exam­ple, tou­rist post­cards of impor­tant land­marks mailed “home,” best day of week for attack (Sun­day), best time of day (early mor­ning), best Oahu flight gate­way for reaching Pearl Harbor (via Kole­kole pass), loca­tion of mili­tary assets in and around Hono­lulu the capital, etc.

Right: Aerial view of the first blows striking Amer­i­can battle­ships moored at Battle­ship Row as seen in this captured Japa­nese photo­graph taken during the initial moments of the Japa­nese air attack on Pearl Harbor. A water spout caused by an exploding bomb appears near the stern of the battle­ship in the middle of the photo.

Left: Aircraft prepare to launch from the Imperial Japanese Navy aircraft carrier Akagi during the December 7, 1941, attack on Pearl Harbor, Hawaii.

Right: The forward magazines of USS Arizona explode after she was hit by a Japa­nese bomb on Decem­ber 7, 1941. Swarms of Japa­nese air­craft can barely be seen ove­rhead in the back­ground as tiny dots. The still image is from a color motion pic­ture taken on board the hospital ship USS Solace.

Left: Adm. Yamamoto salutes Japanese naval pilots at Rabaul a few hours before his death. Yama­moto was at the former Aus­tra­lian air­base on New Britain Island (today a pro­vince of Papua New Gui­nea in the south­western Pacific Ocean) to super­vise carrier-based air oper­a­tions during Oper­a­tion I-Go (April 1–16, 1943). I-Go had limited suc­cess in delaying, much less halting, Allied offen­sives in the South Pacific, but Yama­moto never lived long enough to learn that. His plans to con­grat­u­late naval units that had taken part in I-Go and to boast sagging troop morale after Japa­nese defeats on New Guinea (Janu­ary–Febru­ary 1943) and Guadal­canal (February 1943) Islands and at sea (Battle of the Bis­marck Sea, March 24, 1943) were cut short on April 18, 1943, when he and his party were ambushed and killed en route to an air­base off Bougain­ville Island by a squa­dron of U.S. P-38 Lightning fighter aircraft.

Right: Yamamoto was killed on April 18, 1943, age 59, after U.S. naval intel­li­gence decrypted the itin­er­ary of the admiral’s tour in the Solo­mon Islands area, enabling U.S. Army Air Forces Lock­heed P-38s oper­a­ting from Guadal­canal to shoot down his trans­port bomber. His death was a major blow to Japa­nese mili­tary morale during World War II, while it raised U.S. morale. In this painting by Roy Grin­nell, the Mitsu­bishi G4M Betty twin-engine bomber carrying Yama­moto begins a death spiral into the jungle of Bou­gain­ville. Oper­a­tion Ven­geance, as the shoot­down was called, was revenge by U.S. leaders, who blamed Yama­moto for the Decem­ber 7, 1941, air and naval attack on Pearl Harbor that ini­ti­ated the war between Japan and the United States. Source of Grin­nell’s painting WWII History, June 2022.

Japanese and U.S. Naval Preparations on Eve of December 7, 1941