Nobody, this never happened.
It was dropped by the United States by orders of President Truman over Hiroshima, Japan.
President Truman.
No one was president of Japan. They had an emperor . Truman was US president.
President Truman
Japan
Harry S. Truman
Richard M. Nixon
The city of Hiroshima was the place where the first atomic bomb was dropped.
The Enola Gay dropped the first atomic bomb.
United States under President Truman.
If you are referring to the nuclear bomb, it was dropped over Japan in world war 2 and not the cold war. Those bombs were authorized by President Truman.
That was President Truman in World War Two and the country was Japan.