The Man Who Japed by Philip K. Dick

A darkly comic dystopia about a disaffected man who stages a prank against a rigidly moralistic postwar regime—destroying a revered monument to expose the official myths—and finds his joke spiraling into a political scandal that forces him to face state surveillance, shifting public opinion, personal guilt, and the hollowness of enforced virtue as the society scrambles to punish, co-opt, and rewrite the incident.