A common metric on a city’s self reliance is how much it depends on outside suppliers to feed its population. If separated from the outside world, how well (or indeed, how long) would a city last. Take Phoenix, AZ as one example: it exists in a desert. Without oil to fuel a steady stream of transportation, the city would die. It may as well be on the moon. This is a similar type of calculation performed by armies as they lay siege to a city. David Morris authored this paper on Self-Reliant Cities in 1987 where he says “A healthy city is a self-reliant city, capable of determining its own future. The self-reliant city emphasizes holistic planning. Local self-reliance builds a self-confident and engaged citizenry while it strengthens local economies and protects the environment.” There seems to be a need to revisit this analysis on the current global landscape.