Introduction In August 1925, the atomic bomb, which had been ironically called “Little Boy” was dropped on the city of Hiroshima, leaving at least eighty thousand people dead instantaneously. The total number of casualties (people, who died of injuries and radiation) ranges from 90000 to 140000. Main body The question arises of how such a terrible thing could ever happen because it simply cannot be justified in any possible way. Now it seems to be just a horrible nightmare or something entirely inconceivable. However, we have to admit that there were some reasons for Truman to do it. The main purpose of those attacks was to compel Japan to surrender and yield to the Potsdam ultimatum (Misiko 2005, 102). It must also be mentioned that the sites for bombing were very carefully chosen. There were the following criteria: the explosion must cause considerable damage and demonstrate the whole destructive power of the new weapon, therefore such big cities as Hiroshima and Nagasaki were chosen. Naturally, Hiroshima was of some military and industrial importance but as has already been mentioned, it did not pose any threat to the American forces (Hakim 1995, 89). The effects of the bombing were devastating; the explosion had a blast equivalent to approximately 13 kilotons of TNT. According to the official records, at least ninety percent of build-in Hiroshima were either destroyed or considerably damaged. Doctors of the Red Cross mission could not understand what they were dealing with because these symptoms of radiation overdose were almost unknown to them. Dr. Sasaki says that hospitals were teaming with the wounded people, those who managed to survive the short-term effects of the explosion, but after a while, Dr. Sasaki encountered something he had never seen before the effects of radiation. They were blood disorders, vomiting hair shedding. These are the symptoms of leukemia or blood cancer as one may call it. The shortage of supplies and medical instruments also hampered the work of physicians (Hersey 1974, 146). It must be also taken into consideration that the long-term effects of radiation overdose, which was caused by that atomic explosion, are still very noticeable. After the first bombing President Truman said the following words:” If they do not accept our terms, they may expect a rain of ruin from the air the likes of which has never been seen on this earth.” His announcement proves that this attack was to scare the Japanese government into surrendering. Moreover, we cannot say that the disasters of the atomic explosion were unknown to the US government because the first nuclear test was carried out in Alamogordo, New Mexico on July 16. One of the scientists, who witnessed this event, described it in the following way: “the earth had opened and the skies had split or like the moment of creation when the God said “Let there be light”(Hersey 1974, 147) Thus we may conclude that President Truman did not even try to avert this catastrophe. Now at the beginning of the twenty-first century, this catastrophe seems to be something impossible something that will never happen to us. However, we cannot disregard the existing dander, because no one is inured agains