us atomic bombing of japan in 1945

The atomic bombings of Hiroshima and Nagasaki involved two nuclear attacks during World War IIagainst the Empire of Japan by the United States of America under US President Harry S. Truman. On August 6, 1945, the nuclear weapon "Little Boy" was dropped on the city of Hiroshima, followed on August 9, 1945 by the detonation of the "Fat Man nuclear bomb over Nagasaki.
In estimating the death toll from the attacks, there are several factors that make it difficult to arrive at reliable figures: inadequacies in the records given the confusion of the times, the many victims who died months or years after the bombing as a result of radiation exposure, and the pressure to either exaggerate or minimize the numbers, depending upon political agenda.