Zero-Trust

A medieval city was never secured by its wall alone. It had guilds that vouched for their members, letters of introduction carried from town to town, gate guards who knew faces, innkeepers who noticed accents, and neighbours who registered a stranger in the lane before any official did. The wall was one instrument among many, and arguably not the most effective one. What kept the city safe was a dense weave of overlapping trust relationships, most of them informal, all of them cheap (in financial terms). ...