a typical residence on the outskirts of night sakae -- negativ nagasaki. survivors are busy working at the restoration of their homes. this is the endless man-hours of work. two b-29's, two atomic bombs three days apart. two cities. a tabulation of that record speaks for itself. >> next on american artifacts, to mark the 70th anniversary of the bombing of hiroshima and agasaki, japan, we visit museum in washington, d.c. >> i'm a professor of history at american university and the director of the nuclear studies institute. i began our