Final answer:
Truman's main goal in deciding to use the atomic bomb was to save lives and end the war.
Step-by-step explanation:
According to President Harry S. Truman, his main goal in deciding to use the atomic bomb was to save lives and end the war. In the excerpt, Truman discusses his conversations with General Marshall and Secretary Stimson, where they estimated the high number of casualties that would occur if it came to a land invasion of Japan. Truman believed that dropping the atomic bombs on Hiroshima and Nagasaki would bring a quick end to the war and minimize casualties. Therefore, the main goal was to save lives and give the free nations a chance to face the realities of the post-war world.
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