The Making of the Atomic Bomb

“We faced a terrible decision,” Byrnes wrote in 1947. “We could not rely on Japan's inquiries to the Soviet Union about a negotiated peace as proof that Japan would surrender unconditionally without the use of the bomb. In fact, Stalin stated the last message to him had said that Japan would ‘fight to the death rather than accept unconditional surrender.’ Under the circumstances, agreement to negotiate could only arouse false hopes. Instead, we relied upon the Potsdam Declaration.”

The text of that somber document went out by radio to the Japanese from San Francisco; Japanese monitors picked it up at 0700 hours Tokyo time July 27. The Japanese leaders debated its mysteries all day. A quick Foreign Office analysis noted for the ministers that the Soviet Union had preserved its neutrality by not sponsoring the declaration, that it specified what the Allies meant by unconditional surrender and that the term itself had been applied specifically only to the nation's armed forces. Foreign Minister Togo disliked the demand for occupation and the stripping away of Japan's foreign possessions; he recommended waiting for a Soviet response to Ambassador Sato's representations before responding.

The Prime Minister, Baron Kantaro Suzuki, came during the day to the same position. The military leaders disagreed. They recommended immediate rejection. Anything less, they argued, might impair morale.

The next day Japanese newspapers published a censored version of the Potsdam text, leaving out in particular the provision allowing disarmed military forces to return peacefully to their homes and the assurance that the Japanese would not be enslaved or destroyed. In the afternoon Suzuki held a press conference. “I believe the Joint Proclamation by the three countries,” he told reporters, “is nothing but a rehash of the Cairo Declaration. As for the Government, it does not find any important value in it, and there is no other recourse but to ignore it entirely and resolutely fight for the successful conclusion of the war.” In Japanese Suzuki said there was no other recourse but to mokusatsu the declaration, which could also mean “treat it with silent contempt.” Historians have debated for years which meaning Suzuki had in mind, but there can hardly be any doubt about the rest of his statement: Japan intended to fight on.

“In the face of this rejection,” Stimson explained in Harper's in 1947, “we could only proceed to demonstrate that the ultimatum had meant exactly what it said when it stated that if the Japanese continued the war, ‘the full application of our military power, backed by our resolve, will mean the inevitable and complete destruction of the Japanese armed forces and just as inevitably the utter devastation of the Japanese homeland.’ For such a purpose the atomic bomb was an eminently suitable weapon.”

The night of Suzuki's press conference the five C-54's from Albuquerque arrived at Tinian, six thousand miles nearer Japan, while three B-29's departed Kirtland each carrying a Fat Man high-explosive preassembly.

The U.S. Senate in the meantime ratified the United Nations Charter.

The Indianapolis had sailed on to Guam after unloading the Little Boy gun and bullet at Tinian on July 26; from Guam it continued unescorted toward Leyte in the Philippines, where two weeks of training would ready the crew, 1,196 men, to join Task Force 95 at Okinawa preparing for the November 1 Kyushu invasion. With the destruction of the Japanese surface fleet and air force, unescorted sailing had become commonplace on courses through rear areas, but the Indianapolis, an older vessel, lacked sonar gear for submarine detection and was top-heavy. Japanese submarine 1-58 discovered the heavy cruiser in the Philippine Sea a little before midnight on Sunday, July 29, and mistook it for a battleship. Easily avoiding detection while submerging to periscope depth, 1-58 fired a fanwise salvo of six torpedoes from 1,500 yards. Lieutenant Commander Mochit-sura Hashimoto, I-58's commanding officer, remembers the result:

I took a quick look through the periscope, but there was nothing else in sight. Bringing the boat on to a course parallel with the enemy, we waited anxiously. Every minute seemed an age. Then on the starboard side of the enemy by the forward turret, and then by the after turret there rose columns of water, to be followed immediately by flashes of bright red flame. Then another column of water rose from alongside Number 1 turret and seemed to envelop the whole ship — “A hit, a hit!” I shouted as each torpedo struck home, and the crew danced round with joy… Soon came the sound of a heavy explosion, far greater than that of the actual hits. Three more heavy explosions followed in quick succession, then six more.

The torpedoes and following explosions of ammunition and aviation fuel ripped away the cruiser's bow and destroyed its power center. Without power the radio officer was unable to send a distress signal — he went through the motions anyway — or the bridge to communicate with the engine room. The engines pushed the ship forward unchecked, scooping up water through the holes in the hull and leaving behind the sailors thrown overboard who had been sleeping on deck in the tropical heat. The order to abandon ship, when it came, had to be passed by word of mouth.

With the ship listing to 45 degrees frightened and injured men struggled to follow disaster drill. Fires lit the darkness and smoke sickened. The ship's medical officer found some thirty seriously burned men in the port hangar where the aviation fuel had exploded; at best they got morphine for their screams and rough kapok lifejackets strapped on over their burns. They went overboard with the others into salt water scummed with nauseating fuel oil. It was possible to walk down the hull to the keel and jump into the water but the spinning number three screw with its lethal blades chopped to death the unwary.

Some 850 men escaped. The stern rose up a hundred feet straight into the air and the ship plunged. The survivors heard screams from within the disappearing hull. Then they were left to the night and the darkness in twelve-foot swells.

Most had kapok lifejackets. Few had found their way to life rafts. They floated instead in clusters, linked together, stronger men swimming the circumferences to catch sleepers before they drifted away; one group numbered between three and four hundred souls. They pushed the wounded to the center where the water was calmer and prayed the distress call had gone out.

The captain had found two empty life rafts and later that night encountered one more occupied. He ordered the rafts lashed together. They sheltered ten men and he thought them the only survivors. Through the night a current carried the swimmers southwest while wind blew the rafts northeast; by the light of morning rafts and swimmers had separated beyond discovery.

More than fifty injured swimmers died during the night. Their comrades freed them from their jackets in the morning and let them go. The wind abated and the sun glared from the oil slick, blinding them with painful photophobia. And then the sharks came. A seaman swimming for a floating crate of potatoes thrashed in the water and was gone. Elemental terror: the men pressed together in their groups, some clusters deciding to beat the water, some to hang immotile as flotsam. A shark snapped away both a sailor's legs and his unbalanced torso, suspended in its lifejacket, flipped upside down. One survivor remembered counting twenty-five deadly attacks; the ship's doctor in his larger group counted eighty-eight.

They won no rescue. They passed through Monday and Monday night and Tuesday and Tuesday night without water, sinking lower and lower in the sea as the kapok in their lifejackets waterlogged. Eventually the thirst-crazed drank seawater. “Those who drank became maniacal and thrashed violently,” the doctor testifies, “until the victims became comatose and drowned.” The living were blinded by the sun; their lifejackets abraded their ulcerating skin; they burned with fever; they hallucinated.

Wednesday and Wednesday night. The sharks circled and darted in to foray after flesh. Men in the grip of group delusions followed one swimmer to an island he thought he saw, another to the ghost of the ship, another down into the ocean depths where fountains of fresh water seemed to promise to slake their thirst; all were lost. Fights broke out and men slashed each other with knives. Saturated lifejackets with waterlogged knots dragged other victims to their deaths. “We became a mass of delirious, screaming men,” says the doctor grimly.

Thursday morning, August 2, a Navy plane spotted the survivors. Because of negligence at Leyte the Indianapolis had not yet even been missed. A major rescue effort began, ships steaming to the area, PBY's and PBM's dropping food and water and survival gear. The rescuers found 318 naked and emaciated men. The fresh water they drank, one of them remembers, tasted “so sweet [it was] the sweetest thing in your life.” Through the 84-hour ordeal more than 500 men had died, their bodies feeding sharks or lost to the depths of the sea.

After making good his escape, submarine commander Hashimoto reminisces, “at length, on the 30th, we celebrated our haul of the previous day with our favorite rice with beans, boiled eels, and corned beef (all of it tinned).”

The day of the I-58's feast of canned goods Carl Spaatz telexed Washington with news: