Chris Wallace’s Countdown 1945 tells the story of the 116 days between Harry Truman’s installation as president of the United States and the nuclear strikes on Hiroshima and Nagasaki. The book’s 32 chapters shift between various locations important to the narrative. As the chapters advance, the time gaps between chapters get smaller and smaller until the final chapters tell the story of only days—or mere hours—at a time. While the book features dozens of figures, it concentrates on three main people: President Truman; the physicist J. Robert Oppenheimer; and Colonel Tibbets, pilot of the strike plane Enola Gay. Throughout the narrative, the key figures wrestle with both the technicalities of their mission and the ethical dilemmas that surround the use of the atomic bomb.

This study guide uses the e-book edition of Countdown 1945: The Extraordinary Story of the Atomic Bomb and 116 Days That Changed the World, published by Avid Reader Press in 2020.

Summary

The narrative opens with Harry Truman’s inauguration as president of the United States following the unexpected death of Franklin D. Roosevelt from heart failure. Truman was sworn in and almost immediately heard about a top-secret war project. Meanwhile, the Manhattan Project was proceeding as planned, with the team of scientists—led by the renowned J. Robert Oppenheimer—anxious about how the new president would approach their work. Their mission: the successful creation of an atomic bomb.

While the scientific team was busy at work, Colonel Tibbets was forming and training a flight squadron to deliver the bomb to its target. After spending many months studying and training at a facility in Utah, Colonel Tibbets became frustrated with the constant waiting and delays. He requested that his team be transferred to the remote Pacific island of Tinian in order to complete their training and await the bombing order. His request was granted, and the team prepared for their departure.

About two weeks after becoming president, Truman learned the details of the Manhattan Project. There were three different primary sites working on the bomb, with the most important being in Los Alamos, New Mexico, where Oppenheimer was leading his team of theoretical physicists in the final stages of their work. Civilians were also involved as aides and part-time workers to ensure the smooth operations of the various teams. At the time, the civilians did not know precisely what the scientific mission was, though the truth would come out after the bombings and many would end up feeling betrayed by their complicity in such an ethically-ambiguous action. Meanwhile, the targets for the attack were chosen.

As the bomb neared completion, officials in Washington debated whether or not they were justified in using a weapon of such radical force. The weapon would invariably be responsible for causing mass casualties, and many victims would be civilians and non-combatants. On the other hand, failing to use the weapon might mean prolonging the war by months or even years, resulting in the loss of hundreds of thousands more soldiers. Using the weapon, however, would mean that the world was now a nuclear threat to itself, and America would need to deal with the fallout.

Meanwhile, the project teams and leaders continued their work. Colonel Tibbets recommended that they modify the B-29 Superfortress bomber planes to be lighter and faster, to make a quicker getaway after the attack. American generals MacArthur and Eisenhower prepared for an invasion of the Japanese mainland, dubbed “Operation Downfall.” The generals were concerned by the massive scale such an undertaking would require: The recent capture of the island of Okinawa had demonstrated just how fierce the fighting would be with the Japanese forces, and they dreaded the idea of combat on Japanese soil.

As the day for testing the weapon drew near, scientists also debated the merits of using such a weapon, with some even creating a petition asking for oversight and strict regulations governing the use of nuclear energy. William Laurence, a New York Times journalist, was asking similar questions while working on a story about the bomb’s development.

With three weeks to go until the attack, President Truman traveled to Germany for the Potsdam Conference, determined to talk Stalin into bringing the Soviet Union into the fight against Japan. While he was there, the atom bomb was tested and considered a massive success. After some debate, Truman ultimately decided that the only way to end the war quickly was to use the weapon. He greenlighted the mission, with the strike scheduled for early August.

On the morning of August 6th, the Enola Gay—Colonel Tibbets’s B-29 Superfortress bomber—took off from the Tinian runway at 2:45 AM. Six hours later, the crew released the bomb over the city of Hiroshima. The resulting devastation was more than any of the flight crew expected, completely laying waste to the city along with miles of Japanese countryside—the mushroom cloud from the explosion rose more than eight miles into the sky. Greeted as heroes on their return to Tinian, the crew members wrestled with their own feelings on what they had accomplished that morning. President Truman learned of the attack’s success while en route to America from Germany, and the White House press secretary announced the event to the world back in Washington, D.C.

Three days later, the second bomb dropped over Nagasaki. Japan surrendered formally five days afterwards on August 14th. With the Japanese surrender, the Second World War officially ended after six years of international conflict and more than 70 million lives lost.