On August 6, 1945 and August 9, 1945 were days in history like no other (Alperovitz 2). Only one country in history has ever used an atomic bomb against another nation, the United States of America, code named the Manhattan Project (Lewis 1). The atomic bombs were being developed to use against Japan towards the end of World War II. The United States was completely justified in dropping the bombs on Japan. President Truman's decision to drop the bombs, "Little Boy" and "Fat Man", on Hiroshima and Nagasaki was because he wanted to end the war quickly with little loss of American life, because it was designed to scare the USSR and because Japan's leaders refused to surrender.
After the devastating attack on Pearl Harbor by Japan, Truman's primary objective was to end the war quickly with little loss of American life. He was looking for a way to end it quickly and painlessly, and was looking for a way to avoid using a bomb. A letter was sent to U.S. .
President Franklin D. Roosevelt by Albert Einstein that described the discovery of a mineral, uranium, and warned him of its potential dangers if they used it to develop something (Walker 24). The Manhattan Project was created by the U.S. government in 1942 so the country could develop an atomic device (Walker 26). So more than 100,000 scientists had been working on the bomb's development, and most of those scientists were prizewinning physicists that it made the Manhattan Project the largest collective scientific effort ever undertaken (Walker 27). On 16 July 1945, the scientists did its first trial of the bomb in the New Mexico desert. President Truman received news of the successful test while negotiating the post-war settlement in Europe at the Potsdam Conference (Grant 22). Truman's goal was to spend less .
on American casualties, so the best solution to accomplish his objective was to drop the bomb on Hiroshima after the intense fire-bombing of about 37 Japanese cities (Langley 17).