The Making of the Atomic Bomb: 25th Anniversary Edition

by Richard Rhodes

The report began with the statement that the committee was concerned with “the matter of possible military aspects of atomic fission” and listed three of those possibilities: “production of violently radioactive materials . . . carried by airplanes to be scattered as bombs over enemy territory,” “a power source on submarines and other ships” and “violently explosive bombs.” Radioactive dust would need a year’s preparation after “the first successful production of a chain reaction,” which meant “not earlier than 1943.” A power source would need at least three years after a chain reaction. Bombs required concentrating U235 or possibly making plutonium in a chain reaction, so “atomic bombs can hardly be anticipated before 1945.”