Countdown 1945: The Extraordinary Story of the Atomic Bomb and the 116 Days That Changed the World

Truman receives word—through an encrypted message—while at the Potsdam Conference in Germany that the nuclear test was a success. Having finally met Joseph Stalin in person, Truman has wrangled a confirmation out of the Russian dictator that the Soviet Union will join the war against Japan by the middle of the next month. The Potsdam Conference is held at the summer home of the former German prince, the Cecilienhof Palace, and while Truman was elected to serve as the chairman of the meeting, he is not happy with how things are going—he is convinced that nothing is going to get done.

On the morning of July 18th, Truman receives another message about the nuclear test that confirms even more details, assuring the president that the use of the bomb will be everything they expected it to be. While at lunch with Churchill, Truman shares the news of their nuclear developments. Later that day, Stalin reports that the Japanese ambassador told him of the emperor’s desire to negotiate an end to the war. Truman is surprised that Stalin had no qualms in sharing this information so quickly and freely, but remains unconvinced that he should share his news of American nuclear capabilities.

Back in Tennessee, all Ruth Sisson can do is wait for the war to finally be over, for Japan to finally surrender, for her Lawrence to return home. At this point it has been over three months since Germany surrendered, yet nothing seems to have changed: “most American soldiers and sailors who’d fought in Europe were still there” (146). It has become obvious to everyone that the war is going to be prolonged as the nation faces the impending reality of having to invade Japan.

The central issue at the Potsdam Conference is now the status of the Japanese and the emperor in the case of their surrender. Japan wants a conditional surrender where the emperor would not be deposed; the Allied forces, however, have demanded an unconditional surrender and cannot back down now. With the development of the nuclear bomb, the possibility of shocking the Japanese into surrender is now a possibility, even though Henry Stimson is beginning to express his concerns to the president about the use of such a weapon in war: “Did [Truman] want to be the man to usher in a new age of human conflict with a terrifying new technology? (151).

Colonel Tibbets was fully convinced of the bomb’s power after the test, and now has his crew running difficult practice runs over Japan “dropping ‘pumpkin bombs’—orange globes that contain 5,500 pounds of high explosives and a proximity fuse that detonates in the air above the target, just like the atomic bomb” (152). Beser is not allowed to participate in the practice runs, since he has specialized knowledge that nobody else can match concerning their radar and radio signals.

The one problem that Tibbets continues to have is interference from General LeMay, his commander, who has no idea the amount of training and preparation that has gone into Tibbet’s mission since it has been kept under such secrecy. LeMay plans to put Colonel William Blanchard in charge of flying the mission, but Tibbets refuses to allow himself to be pushed out of the way, firmly insisting that he will be flying the mission himself. The next day Tibbets assures himself of this fact by bringing Blanchard along on a practice training flight and scaring him half to death. 

Truman has spent more than a week and a half in Germany and knows that he is running out of time to make a decision on the nuclear option. It is now July 24th. He receives word that the bomb will be ready to use in the next eight days. Along with this correspondence, he also finally receives a full report that gives him complete confidence in the weapon’s viability, giving him a backup plan if Japan continues to refuse unconditional surrender. Stimson continues to try talking Truman out of the necessity of an unconditional surrender, but it is to no avail— Truman solicits the names of Japanese cities devoted to war production alone, finding the names of Hiroshima and Nagasaki among them.

Back at Los Alamos, the success of the test is cause for celebration, but it is also a cause for sober reflection: “the device they’d so enthusiastically created would soon incinerate a Japanese city full of men, women, and children” (166). The scientists spend a long time debating the use of the bomb, and even Oppenheimer begins to have serious misgivings.

At this point, Truman has decided that they are going to use the bomb. He receives the news that the designated strike team will go ahead with the attack whenever the weather permits after August 3rd, focusing on one of their predestined targets. The Potsdam Conference is at an end.