The world is nationalistic, jingoistic as you put it, because people have belly-buttons. They are human. Look at the conflicts between different parts of France between the fall of Rome and, say, the Sixteenth Century; they all spoke the same language, differing only in accent, but the Normans and Burgundians, among others, were ready to kill one another at the drop of a hat. For that matter, look at out own Civil War, and various regional differences before and since. We all speak the same language, yet do you believe that a perfect state as achieved totally by local vote would be the same in say, California, Oregon, Georgia and Maine? The differences might not be as large as they once were, but that is largely an effect of radio and TV homogenizing our culture.
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