World War II Day by Day

Tokyo, Japan · March 24, 1945

On this date in 1945 the Japanese Deputy Minis­ter of War, Lt. Gen. Kaneshiro Shiba­yama, in­formed the Japa­nese Diet (Parlia­ment) of the for­ma­tion of a mili­tia for the defense of the Home Islands. A home mili­tia was criti­cal to the nation’s sur­vi­val because 60 per­cent of the roughly 4.6 mil­lion Japa­nese com­bat troops were still stationed aboard. The next month, on April 8, the oper­a­tional plan to defend the home­land, called Ketsu‑Go (“Deci­sive Oper­a­tion”), was issued. As a result of les­sons learned in the South Pacific, the in­tent of Ketsu‑Go was to in­flict enor­mous casual­ties on the in­vaders. In fact, this stra­tegy had been tested most recently on the island of Iwo Jima in Feb­ru­ary and March 1945, where one in three U.S. Marines had been killed or wounded. Japa­nese tena­city in com­bat would, it was believed, under­mine the Amer­i­can public’s will to con­tinue the fight for Japan’s un­con­di­tional sur­render; in­stead, the Amer­i­can public would in­sist on a peace more advan­tageous to Japan than other­wise. Pre­par­a­tions for Ketsu‑Go were to be con­ducted in three phases. The first phase, during which defen­sive pre­pa­ra­tions and com­bat unit or­gan­i­za­tion were com­pleted, con­tinued through July 1945. (Com­bat unit organ­i­za­tion in­volved acti­vating the First and Second General Armies as well as an Air General Army.) The second and third phases were to have ended in Oct­ober, when Japa­nese mili­tary offi­cials fore­cast an Amer­i­can in­va­sion of the is­lands might begin. The latter two phases were never com­pleted because the Amer­i­cans had their own plan for under­mining the enemy’s will to con­tinue fighting—all this with­out any further high-cost air, sea, and ground oper­a­tions en­visioned in Oper­a­tion Down­fall (see map and descrip­tion below) and with­out any direct or behind-the-scenes diplo­ma­tic nego­ti­a­tions that might end with less than uncon­ditional Japa­nese sur­render. The Amer­i­can plan was awe­some and drama­tic and cen­tered on using a new wea­pon, the atomic bomb, two of which blasted, seared, and ir­ra­di­ated tens of thou­sands of com­ba­tants and non­com­ba­tants alike residing in Hiro­shima and Naga­saki on August 6 and 9, respec­tively. The way America de­ci­sively ended the war against Japan remains one of the great controversies in U.S. and Japanese history.

Defending the Japanese Homeland Against the Planned U.S. Invasion, 1945–1946

Above: This map outlines the Japa­nese and U.S. ground forces scheduled to take part in Oper­a­tion Down­fall, the battle for Japan. Two landings were planned: Oper­a­tion Olym­pic, on the south­ern is­land, Kyūshū, set to begin in August 1945, and Oper­a­tion Coro­net, on the main is­land, Honshū, set to begin the following spring. The War Depart­ment staff in Washing­ton esti­mated there would be 250,000–500,000 Amer­i­can casual­ties in an in­va­sion of Japan. Oper­a­tion Down­fall was aban­doned when Japan for­mally sur­ren­dered on Septem­ber 2, 1945, after the U.S. dropped atomic bombs on Hiro­shima and Nagasaki the previous month.

Left: Female students receive training in gun hand­ling as mem­bers of a volu­nteer fighting corps, or Kokumin Giyū Sentōtai, in Tokoro­zawa, now con­sidered a suburb of Tokyo. Governors of pre­fec­tures (states) could con­script all male civil­ians between the ages of 15 and 60 years, and un­married females between 17 and 40. Com­manders were appointed from retired mili­tary per­son­nel and civil­ians with wea­pons experi­ence. The Kokumin Giyū Sentōtai was in­tended as the main reserve, along with a “second defense line,” for Japa­nese forces to sus­tain a war of attri­tion against in­vading forces. After the Allied in­va­sion, these forces were in­tended to form re­sis­tance or guer­rilla war­fare cells in cities, towns, and moun­tains. At this stage of the war, most mili­tia mem­bers were armed with swords or even bam­boo spears due to the lack of modern weaponry and ammunition.

Right: Student militia at Kujukuri­hama, Chiba, a pre­fec­ture situ­ated east of Tokyo across Tokyo Bay. Some 28 mil­lion men and women were con­sidered “com­bat capable” by the end of June 1945; yet only about 2 mil­lion were re­cruited when the war ended, and most of these never exper­i­enced com­bat owing to Japan’s sur­render before the Allied invasion of the Japanese home islands could proceed.

Newsreel Documenting Japan’s Unconditional Surrender on Board the USS Missouri, September 2, 1945