Why do people need guns?

I know the second amendment is there but that's just for the federal government to follow. Why haven't state governments completely banned guns yet? What do people use them for? Take guns away from policemen too.
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If you want to talk about the supremacy of the constitution why not mention the supremacy of the king of england. Lol
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Im more concerned with how to lessen the number of criminals. Usa has the biggest prison population in the world. y'all are all about shooting people because they need to rob. Most of the criminals you wish to murder are dull, skilless, and undisciplined.$7.50 minimum wage is just one of many laws here that synthesizes criminals. Usa proves you can brainwash an entire nation to be psychopathic, yet y'all are missing the actual coldness of psychopaths.. pussies.
Why do people need guns?
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