Why do governments exist? One major reason is that they create rules. But what rules are necessary or desirable? That is open to question, and different types of governments have certainly created a wide variety of rules. A country, then, needs to not only protect its citizens from one another, but it needs to organize to prevent outside attack. Sometimes they have built Great Walls and guarded them carefully from invaders. Other times they have led their followers to safe areas protected by high mountains, wide rivers, or vast deserts. Historically, they have raised armies, and the most successful ones have trained and armed special groups to defend the rest. Indeed in the twentieth century, governments have formed alliances and fought great world wars in the name of protection and order.
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