Assignment task:
President Truman elected to use the atomic bomb in order to end the war with Japan. From his perspective as Commander-in-Chief, using all of the information at his disposal, this was the best and most humane decision he could make. Indeed, it was the surest way to end the war quickly and thus save American lives. Despite his reasoning, though, Truman has been absolutely vilified in the court of public opinion ever since; he's oftentimes labeled as a murderer guilty of crimes against humanity.
So you must now answer one question: prosecution or defense? One which side do you stand? You can be either, so it simply boils down to your interpretation of the pertinent evidence. If you think Truman's decision to deploy the bomb was wrong, for whatever reason, then prosecute him for his crimes. Conversely, if you think his actions were right, for whatever reason, then stand in his defense. Outline your fact-based argument; incorporate specific examples whenever possible.