The Penultimate Truth
by Philip K. Dick
In the future, most of humanity lives in massive underground bunkers, producing weapons for the nuclear war they've fled. Constantly bombarded by patriotic propaganda, the citizens of these industrial "anthills" believe they are waiting for the day when the war will be over and they can return aboveground. But when Nick St. James, president of one anthill, makes an unauthorized trip to the surface, what he finds is more shocking than anything he has been told.