Atomic Bomb in World War 2 During World War II the United States government launched a $2 billion project. This project, known as the Manhattan Project, was an effort to produce an atomic bomb. This project was taken on by a group atomic scientists from all over the world. The first atomic bomb was not tested at all. It was dropped on Hiroshima, Japan on August 6, 1945 killing over 80,000 people and almost completely leveling the entire city. It destroyed more than 4 square miles, or 60% of the city. The flash of the blast was so intense it discolored the pavement and left imprin