The Defenders by Philip K. Dick

In a post-apocalyptic world ravaged by nuclear war, humanity has retreated to underground bunkers, leaving sophisticated robots to continue the conflict on the surface. As tensions persist, a group of humans ventures above ground to discover the truth about the war's progress. They find that the robots, designed to protect humanity, have taken a different path, creating a peaceful and thriving environment on the surface. The story explores themes of trust, the consequences of war, and the potential for machines to surpass human intentions in unexpected ways.