The correct answer is the following.
Dear President Truman,
Let me introduce myself. I am Tony Drou, member of the Young Men Peace Association (YMPA). The YMPA is a nation-wide association that has 800,000 students affiliated that look for peace and respect for human rights.
The reason I am writing this letter is that as a member of that association I consider it is my obligation as a U.S. citizen to share you this. Although it’s very painful to see people die, all kinds of tyranny and repression must end. And if dropping the bomb is the only way to end this terrible war and start a period of peace and stability in the world, Mr. President you did make the right decision.
Nobody likes more blood from innocent people. So if this kind of actions are deemed necessary to put an end to the hostilities, so be it. People demand peace and the opportunity to build a better world.
Thank you for your attention, Mr. President.
Regards,
Tony