"Photographers in the Physical Damage Division of the Survey were tasked with documenting the broad extent and mundane detail of atomic destruction for later analysis by architects and civil engineers. The images they made helped form the basis for civil defense architecture in the U.S., especially in the early part of the Cold War, from the design of bomb and fallout shelters to suburbanization."
Read more: http://lightbox.time.com/2011/05/19/hiroshima-ground-zero-1945/#ixzz1Mu6RSnHX