The first foreign trip Truman makes as president is to Germany for the Potsdam Conference, a summit held with Winston Churchill and Joseph Stalin. Truman can think of nothing but the impending nuclear weapon test. Nevertheless, Truman intends to recruit the Soviet Union into the war against Japan, as Stalin had promised before to join in. Waiting for Stalin to arrive, Truman tours Berlin and sees firsthand the destruction that has been wreaked upon the city. He is “shocked by the devastation” (122).

Meanwhile, in New Mexico, Donald Hornig sits atop a high tower, standing watch over the bomb as they wait for morning to come to finally test the first atomic bomb. A special steel tower was constructed for the purpose of dropping the bomb for the test run, as well as several concrete bunkers put up for the sake of observation. Oppenheimer is filled with anxiety, but as morning dawns and the time for the test approaches, he and the rest of the team prepare for the final moments and the long-awaited test run. At the precisely timed moment, the bomb is dropped and ignited: “With the explosive power of 20,000 tons of TNT, a light ‘brighter than the noonday sun’ was seen two hundred miles away, while the sound carried close to a hundred miles” (131), resulting in a crater in the desert six feet deep and over one thousand feet in diameter.