Vannevar Bush updates President Roosevelt on the state of atomic bomb technology: 1) several kilograms of Pu239 or U235 can create an explosion of several kilotons; 2) there are four possible methods of preparing the fissile material: electromagnetic U235, diffusion U235, centrifugal U235, or chain reaction production of Pu239; it is not yet known which method is preferable; 3) a sizable industrial production plant is feasible; 4) the whole thing can begin soon enough to be completed to be of military use in the ongoing conflict. The president approves and gives instructions for funding the undertaking, which will soon become the Manhattan Project. It is an effort, the industrialization of a cutting-edge technology in 24 months, which normally in peacetime under “normal” circumstances would have taken decades.
