Can you imagine _war_ in this world? At first armies can march in one direction of the ring or the other, with every natural defense point being sort of a Ther

Can you imagine _war_ in this world? At first armies can march in one direction of the ring or the other, with every natural defense point being sort of a Thermopilae situation Then, technology progresses and certain machines may allow smaller groups to traverse outward for limited periods of time. Analogous to our submarines? Would then flight make the world "flat" and globalized? They can't lay cables across the scorching dor icy deserts, so worldwide comm must either follow the ring or be satellite-based