A theme is a universal truth about life or mankind that a work of art seeks to convey. A literary work can have many themes. Three themes in Nadine Gordimer's short story are explained below.
1. Living in fear creates a prison of one's own making. In the story frame and in the bedtime story the narrator tells herself, the characters allow fear to dictate how they act. The narrator, lying in bed, is "a victim already." She feels trapped in her room, unable to rest or sleep but also unable to rise up and put her fears to rest. The family, attempting to protect themselves from rioters, murders, and burglars, enclose themselves behind walls, bars, and finally an ugly Auschwitz-like coil. What they do to their property symbolizes what they are doing to their souls and spirits—cutting themselves off and stunting their lives because of their fears.
2. Avoiding and withdrawing from what we fear, especially if it is fear of "the other," cannot solve the problem. The more effort the family makes to escape from the racial/ ethnic group they distrust, the more the problems between their community and the other community grows. The wife's instinct to reach out to the other group with compassion is quickly squelched, yet that is the only glimmer of possibly bringing an end to the escalating fear and isolation the family feels.
3. To live "happily ever after" requires more than material possessions. Looking for root causes of the tragedies that occur in the story, we must follow the money, and we find that love of money is the root of this evil. The family has arrived at their "house in a suburb" where they "had a car and a caravan trailer for holidays, and a swimming-pool." This good life that they have achieved requires protection. They fear losing it, so they insure it and participate in Neighborhood Watch. They can't insure against riot, though, so they go to drastic measures to make sure their property can't be taken from them. In the family's obsessive desire to protect their material wealth, their relationships suffer. The mother-in-law is a "witch," and they are unable to show basic human kindness to outsiders that would enrich their own souls and spirits. Ultimately, they lose their most precious "possession," their son, because of their fixation on protecting their material goods.
These strong themes of fear, prejudice, and materialism make "Once upon a Time" a powerful short story.