Learn how a presidential decision to begin a huge national science project changed ordinary people's lives in this clip from The Bomb. After president Franklin Roosevelt was alerted to the potential of a Nazi nuclear bomb, he authorized a nuclear project code-named "Manhattan". It required large numbers of engineers, scientists, and workers, and had to be conducted in utmost secrecy. Ordinary Americans all over the country were called to participate, but were not told what they were joining. Even though the war threatened America's survival, 1940s social attitudes and prejudices meant that few women were scientists, and those who were faced resistance when they tried to participate.