Aboard the U.S. Carrier Shangri-La · July 14, 1945

On this date and the next in 1945, less than four months after the start of Opera­tion Star­va­tion—the joint U.S. air and naval effort to strangle Japa­nese mari­time traf­fic by the aerial mining of Japan’s har­bors and straits—Navy air groups destroyed over half the train ferries between the north­ern Japa­nese island of Hok­kaido and the main island of Honshū, where most of Japan’s indus­try and rail lines were located. Almost over­night the amount of Hok­kaido coal delivered to Honshū fac­tories dropped more than 80 per­cent, seriously crip­pling Japa­nese indus­try. Literally between a rock and a hard place, Japan saw its imports of selected com­modi­ties, in­cluding coal and food­stuffs, which totaled over 20 million tons in 1941, cut in half in 1944 and plum­met to 2.7 million tons in June 1945. Vice Admiral Paul Wen­neker, Ger­man naval attaché (1940–1945) in Tokyo, believed that it was sub­marine war­fare that brought Japan to its knees. Wen­neker had per­sonal know­ledge of the U.S. sub­marine block­ade of Japan, for he was in charge of the naval opera­tion that brought Ger­man goods such as opti­cals, machine tool equip­ment, and plans for air­planes to Japan in return for vital Asian mate­rials like qui­nine and tin. “But this was not so easy an arrange­ment because of the Ameri­can sub­marines on the route between Japan and the south,” by which he meant Pe­nang or Sin­ga­pore on the Malay Penin­sula. “It was ter­rible,” he told his Ameri­can inter­ro­gator. “Some­times the entire con­voy including all my mate­rial would be lost. It seemed that nothing could get through.” Yes, the U.S. sub­marine block­ade had been respon­sible for the drop in im­ports through the early part of 1945; how­ever, it was the B‑29 air-dropped mines of Opera­tion Star­va­tion, over­seen by Maj. Gen. Curtis LeMay, that provided the tip­ping point. By August 1945, the month in which Hiro­shima and Naga­saki were vapor­ized, the coun­try had less than half the food and raw mate­rials needed to con­tinue the fight. After Hiro­shima and Naga­saki Japan’s Emperor Hiro­hito (post­humously referred to as Emperor Shōwa) had no fight left, which made all the differ­ence. In a royal under­state­ment, Hiro­hito told his sub­jects on August 15: “The war situ­a­tion has devel­oped not neces­sarily to Japan’s advan­tage.” To con­tinue the fight would “result in an ulti­mate collapse and oblit­eration of the Japanese nation.”

Getting Japan’s Attention: Operation Starvation

B-29 aerial mining of Japanese waters, 1945 M26 sea mine used by Operation Starvation

Left: Beginning on March 27, 1945, B‑29s assigned to Opera­tion Sta­rva­tion dropped 1,000 para­chute-retarded influ­ence mines with mag­netic and acous­tic exploders. The initial sortie was followed up by 1,528 more. Some models of mines had water-pres­sure-dis­place­ment exploders. Aerial mining proved the most effi­cient means of destroying Japa­nese shipping during the war. In terms of damage per unit of cost, it sur­passed the stra­tegic bombing and the U.S. submarine campaigns.

Right: A 1,000 lb M26 sea mine being dropped by a B‑29, 1945. The Twen­tieth Air Force laid 12,135 mines in 26 fields on 46 sep­a­rate mis­sions. Even­tually most of the major ports and straits of Japan were repeatedly mined, severely dis­rupting Japa­nese logis­tics and troop move­ments for the remainder of the war. The mines sank or damaged 670 ships totaling more than 1,250,000 tons.

Hirohito’s surrender rescript, August 1945 UU.S. leaflet airdropped over Japan, August 1945

Left: Imperial rescript from Emperor Hirohito ordering Japan’s capitu­la­tion and the end to World War II. It was written on August 14, 1945, recorded on a phono­graph record, and broad­cast to Japa­nese citi­zens at noon on August 15. In his Gyo­kuon-hōsō (lit. “Jewel Voice Broad­cast”), Hiro­hito admonished his sub­jects to “endure the unen­dur­able and bear the unbearable.”

Right: A leaflet dropped from a B-29 on Japan after the bombing of Hiro­shima. Trans­la­tion: Notice to the Japa­nese People! Evacu­ate the city immedi­ately. What this leaf­let con­tains is ex­tremely im­por­tant, so please read care­fully. The Japa­nese peo­ple are facing an ex­tremely im­port­ant autumn. Your mili­tary leaders were pre­sented with thir­teen articles for sur­render by our three-coun­try alli­ance to put an end to this unprof­it­able war. [The refer­ence here was to the Pots­dam Declara­tion issued by the U.S., Great Britain, and Nation­alist China on July 26, 1945.] This pro­posal was ignored by your army leaders. Because of this the Soviet Republic inter­vened. In addi­tion, the United States has devel­oped an atom bomb, which had not been done by any nation before. It has been deter­mined to em­ploy this fright­ening bomb. One atom bomb has the destruc­tive power of 2000 B‑29s. This fright­ening fact should be under­stood by you by observing what kind of situ­a­tion was caused when only one was dropped on Hiro­shima.

1945 U.S. Army Air Forces Strategic Bombing of Japan