A civil war is a dreadfully destructive tragedy. Ask the people of Bosnia, Sudan, Cambodia or Lebanon. In a way, the rise of the militia movement in the United States is understandable. The United States is physically big and heavily armed. The country is connected in many complex ways with every part of the world.
Government is big and the bureaucracy is big.
The individual citizen is small and is likely to feel rather powerless and unable to have much impact on what happens in the country. Powerlessness breeds frustration and anger. The frustrated and angry citizen sees that the government has all the coercive force at its disposal - all, that is, except for the guns that citizens have a right to keep. That right then begins to seem very precious. The regular armed security personnel of the nation, who have been deputised by the people, have their job to do and it is a somewhat dangerous job.