Why did Truman agree to use the atomic bomb

America had the bomb. Now what?

When Harry Truman learned of the success of the Manhattan Project, he knew he was faced with a decision of unprecedented gravity. The capacity to end the war with Japan was in his hands, but it would involve unleashing the most terrible weapon ever known.

American soldiers and civilians were weary from four years of war, yet the Japanese military was refusing to give up their fight. American forces occupied Okinawa and Iwo Jima and were intensely fire bombing Japanese cities. But Japan had an army of 2 million strong stationed in the home islands guarding against invasion.

A "mushroom" cloud rises over the city of Nagasaki on August 9, 1945, following the detonation of "Fat Man." The second atomic weapon used against Japan, this single bomb resulted in the deaths of 80,000 Japanese citizens.

For Truman, the choice whether or not to use the atomic bomb was the most difficult decision of his life.

First, an Allied demand for an immediate unconditional surrender was made to the leadership in Japan. Although the demand stated that refusal would result in total destruction, no mention of any new weapons of mass destruction was made. The Japanese military command rejected the request for unconditional surrender, but there were indications that a conditional surrender was possible. Winston Churchill, Harry Truman, and Josef Stalin meet at the Potsdam Conference. They discussed the post-war order and peace treaty issues.