The Manhattan Project, conducted between 1942 and 1946, aimed to develop the first atomic bomb, resulting in the bombing of Hiroshima and Nagasaki. Led by General Leslie R. Groves and J. Robert Oppenheimer, the project involved complex scientific efforts and significant military oversight, ultimately leading to the dawn of the atomic age. The aftermath raised ethical questions regarding the justification of the bombings and their impact on the war and subsequent Cold War dynamics.

1. The Manhattan Project Ben Traquair Brian Wittenberg Ian Boelts

2. Overview Project to develop first Atomic Bomb Specifically between 1942-1946 Resulted in Destruction of Hiroshima and Nagasaki End of war with Japan

3. Who Under jurisdiction of the US Army Corps of Engineers General Leslie R. Groves J. Robert Oppenheimer Einstein Fermi FD Roosevelt

4. Einstein and The Bomb Szilard consults Einstein about German Potential The Roosevelt letter-1939 Leads to Uranium Committee Severe guilt

5. J. Robert Oppenheimer Physics professor at UC Berkeley Invited to work on the “Uranium Committee” Unlikely Candidate for Groves’ second in command Seen as being best man to lead the diverse team "Now I am become Death, the destroyer of worlds."- J.R.O.

6. L.R. Groves Took over in 1942 for J. Marshal Marshal was moving too slow Coined “Manhattan” name Prioritized research and development well

7. L.R. Groves Chose development sites and targets Involved in acquiring information about German research Shadowed project in unprecedented security Unable to prevent Russian espionage

8. Fermi Italian Physicist Chicago Pile-1 The first self sustained nuclear reaction

9. Development American and British attempts as early as 1939 1942 control was transferred to US military More serious efforts 1944 Productions plants were constructed

10. Development Multi-pronged pursued multiple theories and designs Plutonium and Uranium The plutonium came from Fermi’s reactors Very Secretive

11. Tritinity 1945- Los Alamos “Fat man” Testing the implosion design Beginning of Atomic Age Disproved “Nuclear Ignition of Atmosphere”

12. The Bombs Two types of Fission design “Fat man” vs. “Little boy” Implosion and Gun type Uranium-238

13. Plutonium Bomb Plutonium-239 Hanford site refined the plutonium Nagasaki

14. Uranium Uranium-235 Oak Ridge site refined the Uranium Hiroshima

15. Arms Race “Tube Alloys” “Soviet Atomic Bomb Project” Soviet espionage The Chevalier Incident

16. Hiroshima/Nagasaki 1945

17. Aftermath

18. Results Arguably most important scientific advance of the century 200,000 Japanese people in a matter of seconds

19. Post-War Two Scientists irradiated to death accidentally Atomic Energy Act of 1946 United states Atomic Energy Commission

20. Discussion time Knowing what you do about Pearl Harbor and the Japanese habits during the war, was the destruction of the two cities justified? How do you think the remainder war would have been different had the United States not dropped the Bomb? Had the bomb not been dropped how would the Cold War period be different?