Although some within the U.S. military were nervous about the use of the new weapon against Japan, Truman was convinced that the bomb was the correct and only option. Six months of intense firebombing of 37 Japanese cities had done little to stop the Japanese, and Japan continued to ignore the demand for unconditional surrender. As a result, Truman saw the use of the atom bomb as the best means of forcing Japan to surrender and ending the war. The alternative—an Allied invasion of the Japanese home islands—was expected to cost hundreds of thousands of casualties.
The effects of the attack were devastating. The Japanese surrender on August 15—just six days after the bomb in Nagasaki—ended World War II. Yet the shocking effects soon led many to doubt the use of this weapon. And the long-term effects of the radiation caused by the bomb—unknown by scientists at the time—still affect the people of Hiroshima and Nagasaki today.
The first western scientists, servicemen, and journalists to arrive on the scene produced vivid and heartrending reports describing a destroyed landscape filled with hideously burnt people, coughing up and urinating blood and waiting to die. One survivor of the bomb, Yoshitaka Kawamoto, described the horrifying scene:
All I can remember was a pale lightning flash for two or three seconds. Then, I collapsed. I don’t know how much time passed before I came to. It was awful, awful. The smoke was coming in from somewhere above the debris. Sandy dust was flying around. . . . I crawled over the debris, trying to find someone who was still alive. Then, I found one of my classmates lying alive. I held him up in my arms. It is hard to tell, his skull was cracked open, his flesh was dangling out from his head. He had only one eye left, and it was looking right at me. . . .
I, so, was running, hands were trying to grab my ankles, they were asking me to take them along. I was only a child then. And I was horrified at so many hands trying to grab me. I was in pain, too. So all I could do was to get rid of them, it is terrible to say, but I kicked their hands away. I still feel bad about that. I went to Miyuki Bridge to get some water. At the river bank, I saw so many people collapsed there. . . . I was small, so I pushed on the river along the small steps. The water was dead people. I had to push the bodies aside to drink the muddy water. We didn't know anything about radioactivity at that time. I stood up in the water and so many bodies were floating away along the stream
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