And more to your point, I (the collective manifestation of the citizenry) have leverage against a government that does as you suggest by keeping firearms in my possession, being proficient in their use, and advocating (through constitutionally protected peaceable means) for my right to do so. This is one of the functions of the second amendment: to act as a check on a government that overreaches. Tax-dodging nuts holed up in the mountains notwithstanding, governments need checks on their powers that have teeth in them. It's kind of like the British monarchy: on paper, the monarch is supreme. In practice, it's understood what would happen if he or she tried to assert that supremacy, so they don't.