If you're going to make a militia, you make it big and fast. Legally you have little or no standing once you declare yourself militia or take any action as one. Morally you have every right to do so. The safety vested in (when) doing so should be backed up by its own inherent force. You would need articles of operation, A statement of intent would be good (related to your rationale for assembling), chains of command, a separate military legal system, a code of military justice, and of course men and arms to fill command, judicial and ranks. At that point you are a standing militia, legally entitled to challenge any component of government, even at force of arms, given proper justification (a cassus belli). I think 10k men per state would be more than sufficient... We keep saying 3%.. It would take a fraction of that. People are insouciant.