Potsdam, Germany July 21, 1945

The “Big Three” Allies opened their victors’ confer­ence on July 17, 1945, in an undamaged suburb 15 miles from Berlin. Two drama­tic uncon­di­tional surren­ders by the heads of Germany’s armed forces a week after the April 30 sui­cide of German dic­ta­tor Adolf Hitler had encour­aged the govern­ment heads of the U.S., Great Britain, and the Soviet Union to assem­ble with their polit­i­cal and mili­tary advisers in Pots­dam as quickly as pos­si­ble. The dele­gates’ weighty task: estab­lish a peace­ful geo­polit­i­cal and eco­no­mic post­war order in the ruins of war-torn Europe. Weighing slightly less on the dele­gates’ minds—yet more so on the minds of Amer­i­cans on the home front and their loved ones assem­bled on war­ships and in island gar­ri­sons off the coast of Japan—was how to end the still-raging war with Germany’s hold-out mili­tary part­ner as expe­di­tiously as pos­si­ble and establish a similar postwar order in the Asia Pacific region.

Exactly how to end the war with Japan gene­rated intense debate. The geo­graphy of the island nation com­pli­cated attempts at inva­sion. Honshū, Japan’s most popu­lous island and the location of its capital, Tokyo, was Japan’s largest city as well as home to the quasi-divine Emperor Hiro­hito (post­humously referred to as Emperor Shōwa). Unlike Hitler, who sur­vived multi­ple of attempts by his mili­tary to assas­si­nate him, Hiro­hito had no such domes­tic foes until the last hours of the Pacific War. Besides, Hiro­hito had come to viewed by most U.S. mili­tary offi­cials as the only figure with the requi­site credentials to engineer Japan’s surrender.

The emperor and his fire-breathing war­lords needed some­thing out­side the tradi­tional war book to induce them to the peace table. U.S. phys­i­cists and mili­tary planners were busy secretly building a bomb of unknown capa­bil­ity that might or might not end World War II with a bang. At the same time the new Amer­i­can pres­i­dent, Harry S. Truman, was pur­suing a stra­tegy to enlarge the con­flict. Step 1: entice war­time ally Joseph Stalin, head of the Soviet Union, to aban­don his nation’s non­ag­gres­sion pact with Japan. (Agree­ment appeared close in Febru­ary 1945 at a Big Three con­fer­ence at Yalta in the Soviet Crimea.) Step 2: con­vince Stalin to declare war on Japan. On this date, July 21, 1945, stra­tegy-con­firming news reached Truman in Pots­dam. U.S. Sec­re­tary of State James Byrnes handed the pres­i­dent a news sum­mary that showed Amer­i­can press opin­ion strongly sup­ported the Soviets’ entry into the war—a war U.S. mili­tary advi­sers esti­mated might cost all bellig­er­ents hun­dreds of thou­sands more deaths and drag on for upwards of 16 months.

Despite overwhelming public and media sup­port for the Red Army entering the Paci­fic fray, a few voices in the State, War, and Navy depart­ments raised late-term con­cerns. All for naught. Stalin told Truman on Day 1 of the Pots­dam Con­fer­ence that his mili­tary would invade Chi­nese Man­chu­ria (Japa­nese puppet state Man­chu­kuo) by mid-August 1945. Although Soviet con­di­tions appeared modest to Truman, in real­ity Stalin saw a stra­te­gic oppor­tu­nity to turn the tables on the Japa­nese by regaining Chi­nese assets Czarist Russia had lost following the disastrous Russo-Japanese War in 1904–1905.

On August 6, 1945, as diplomatic nego­ti­a­tions dragged on, a single U.S. B‑29 Super­for­tress dropped a fear­some bomb on Hiro­shima that killed 70,000 Japa­nese out­right. Three days later, on August 9, 40,000 resi­dents of Naga­saki died out­right in a second atomic blast. Earlier that day Soviet armed forces invaded Man­chu­ria; Stalin had kept his word. Japan suddenly found itself in a tight spot: Soviet troops making a bee­line for the China coast, Amer­i­can B‑29s swarming over­head loaded for bear. On August 14 Emperor Hiro­hito recorded his uncon­di­tional sur­ren­der rescript, which was broad­cast to the world the next day. The con­flict ended, Japan’s formal sur­ren­der was recorded in a solemn cere­mony on the deck of the U.S. battle­ship Missouri in Tokyo Bay on September 2, 1945.

Potsdam Conference, July 17 to August 2, 1945: Shaping the Future of Europe and Japan

Potsdam Conference "Big Three" (l–r) Churchill, Truman, StalinPotsdam Conference: Shapers of post-World War II Europe and Japan

Left: Codenamed Terminal, the Potsdam Conference was the third Big Three con­fer­ence between a U.S. Pre­si­dent but the first between Harry S. Tru­man (seated center), British Prime Minis­ters Win­ston Chur­chill (to Truman’s right) and his post­war suc­ces­sor Cle­ment Att­lee (not seen), and Soviet Pre­mier Joseph Stalin. The 17‑day con­fer­ence got under­way on July 17, 1945, in Berlin’s rela­tively undamaged, picture-post­card suburb of Pots­dam and its eastern district of Babels­berg. It ended on August 2, 1945. The discus­sions were inter­rupted three-quarters­way through as the heads of govern­ment awaited late returns of the July 5 British parli­a­men­tary elec­tions. Chur­chill lost by a land­slide and was replaced by his polit­ical oppo­nent, Cle­ment Att­lee, who had been at the con­fer­ence since its opening. The dele­gates resumed their nego­ti­a­tions on July 28. Chief among the agenda items pushed by the con­fer­ees was the estab­lish­ment of a new post­war order in Central and Eastern Europe and in the Asia Pacific area that would rec­tify defects of the past three decades that followed the con­clu­sion of the Ver­sailles Con­ference in Paris (January 18, 1919 to January 21, 1920).

Right: Heads of government, foreign ministers, various advisers, and inter­preters sit around the large oak table that domi­nated the con­fer­ence room in Potsdam’s sprawling Cecilien­hof Palace, named for Cecilia, the wife of Kaiser Wilhelm II’s son, Crown Prince Wilhelm. The photo was taken before Attlee (bald head lower left) suc­ceeded Chur­chill (bottom left of center) as prime minis­ter of Great Britain and head of govern­ment. Truman sits five chairs to the right of Chur­chill. At Stalin’s sug­gestion Truman was made con­fer­ence chair­man. It was on July 17, 1945, during the first of 13 ple­nary ses­sions, that Stalin announced his deci­sion to declare war on Japan “with no strings attached,” as Truman later told his wife, Beth, in a letter home. On another occa­sion Truman bragged to his wife: “I can deal with Stalin . . . He’s honest but smart as hell.” Truman proph­e­sied that with the Soviet Union in the fight against Japan “we’ll end the war a year sooner now, and think of the kids who won’t be killed! That is the important thing.”

Hiroshima Chamber of Industry and Commerce Building (Genbaku Dome)Nagasaki’s Mitsubishi Steel and Armament Works after destruction

Left: The Hiroshima Chamber of Industry and Com­merce Building was the only building remotely close to standing near the epi­center of the atomic bomb blast of August 6, 1945. Known today as the Gen­baku (“Atom Bomb” in Japa­nese) Dome, it was left unre­paired by its citi­zens as a reminder of the unprec­e­dented event that befell their city. It sits in a lush park, the Hiro­shima Peace Memo­rial Park, sur­rounded by a metrop­o­lis of one million people. For many visitors the memo­rial park and museum are hallowed ground.

Right: The still-standing smokestacks of Nagasaki’s sprawling Mitsu­bishi Steel and Arma­ment Works. The plant was located about 2,500 ft down­river from ground zero. Naga­saki’s hilly ter­rain tempered the bomb’s destruc­tive effects, where­as Hiro­shima was flat and open and thus suffered much greater devas­ta­tion. The horri­fic effect of the atomic bombings on two major Japa­nese cities, plus the threat posed by Soviet armies approaching the Chi­nese coast oppo­site the Japa­nese home islands, com­pelled Hirohito to order his country’s surrender.

Japanese surrender delegation, September 2, 1945MacArthur opening surrender ceremony, September 2, 1945

Left: The 11-member Japanese delegation of civilians and mili­tary offi­cers shortly after their arrival on board the USS Missouri, Sunday, Septem­ber 2, 1945. For the first time in its history Japan was sur­ren­dering to both a foreign power and an occupying power. Leading the dele­gation was Foreign Affairs Minis­ter Mamoru Shige­mitsu (top hat and cane). In 1948 Shige­mitsu was sen­tenced to seven years im­pri­son­ment by the Inter­na­tional Mili­tary Tri­bu­nal for the Far East. Paroled in 1950 Shige­mitsu became Deputy Prime Minister of Japan in 1954.

Right: Dressed in khaki and an open-neck shirt, General of the Army Douglas Mac­Arthur, Supreme Allied Com­mander, opened the 20‑minute sur­render cere­mony on the Missouri’s star­board veran­da deck precisely at 9 a.m. Forty-three high-ranking offi­cers from eight Allied powers lined up behind him. Slowly Mac­Arthur intoned, “We are gathered here, repre­sen­ta­tives of the major warring powers, to conclude a solemn agree­ment where­by peace may be restored . . . It is my earnest hope and indeed the hope of all man­kind that from this solemn occa­sion a better world shall emerge out of the blood and car­nage of the past—a world founded upon faith and under­standing, a world dedi­cated to the dig­nity of man and the ful­fill­ment of his most cherished wish—for freedom, tolerance, and justice.”

Scenes of Postwar Berlin and Arrival of the “Big Three” in Potsdam