The Manhattan Project consisted of a number of labs in secret locations around the country, each charged with solving a different aspect of bomb construction. Enrico Fermi's lab at the University of Chicago was dedicated to creating the world's first controlled nuclear chain reaction. Meanwhile, huge processing factories in Tennessee attempted to manufacture the large quantities of radioactive material that the scientists would require. The bomb would need to use one of two materials: uranium 235 (U-235) or plutonium. Both were very rare. U-235 is an isotope of uranium, and, unfortunately, ninety-nine percent of uranium is U-238, which meant that scientists needed to find an efficient way of extracting enough U-235 to create a nuclear explosion.
But the core of the project was the design and creation of the bomb itself, a task which was entrusted to a secret laboratory in an isolated location, directed by an untested administrator: Robert Oppenheimer. Leslie Groves had met Oppenheimer shortly after taking control of the Manhattan Project and was deeply impressed by the young physicist. Although Oppenheimer had never been in charge of anything larger than a class of physics students, and although the military was still suspicious of his ties to communism, Groves placed Oppenheimer in charge of the bomb design program.
Groves, obsessed with keeping the Manhattan Project a secret, kept the project decentralized in its early phases, and it was his intent that no group of scientists would ever know what another group was doing. But Oppenheimer objected, saying that this type of secrecy would hinder the scientists' work and slow the project. What was good for security was not necessarily good for science, and eventually Oppenheimer, and science, won out. Groves and Oppenheimer agreed to select an isolated location to which they would bring the country's top physicists, creating a refuge in the middle of nowhere where the scientists could work together and live together. Oppenheimer selected the location himself: Los Alamos.
Los Alamos–a name is now synonymous with the bomb project–was nothing more than a deserted mesa in north-central New Mexico in 1942. Oppenheimer was already familiar with the area, since, in 1928, he and his brother had vacationed in New Mexico and had loved it so much that they bought a cabin there. Now it would be his home for the next several years. Oppenheimer and Groves renovated the building of an old boys' school to serve as a base camp and built a set of cheap barracks that would house the physicists and their families.
The lab was ready–but would the physicists come?
Oppenheimer set off on a trip around the country to recruit the best scientists he could find. He called upon his current and former students, as well as some of the world's most famous physicists. Many, such as Hans Bethe, Edward Teller, and Niels Bohr, were refugees from Nazi Europe who knew all to well what would happen if Hitler got the bomb before the United States and were only too willing to help prevent that from happening.