The End Of This Day's Business by Katharine Burdekin

Set in a future where women have ended patriarchal rule and built a stable matriarchal society, men live protected but politically powerless lives to prevent a return to male violence and war. The story centers on a leading woman’s conflicted effort to teach her beloved son the history that justifies his subordination, even as she questions the ethics of sustaining power through domination. Through intimate dialogue and political ritual, it explores the costs of security, the seductions of authority, and whether reversing oppression can ever yield true justice.