Every time there’s a guns-related thread, it seems, someone will post something to the effect that the purpose, or a purpose, of the Second Amendment is to allow the people to have guns to “keep the government honest,” or to enable the people to resist a tyrannical government with armed force if necessary, or words to that effect. This is often called the “insurrectionary theory” of the 2nd Am.
This is nonsense. That notion certainly was in the air at the time the Bill of Rights was adopted, but it never found its way into the Constitution. The original text of the Constitution expressly authorizes the POTUS to command all militia, and insurrection is a thing neither protected nor tolerated – it is, rather, a circumstance where the right of habeas corpus may be suspended (though whetehr by the POTUS or Congress is left unclear; Lincoln asserted the power and got away with it, at any rate). Nothing in the 2nd Amendment changes any of that one iota; if it were meant to, it would say so explicitly. The “well regulated militia” clearly is conceived as an arm of government (whether state or federal), not as a countervailing popular force against government (whether state or federal). The only reason there’s anything in the BoR about the militia at all is because the many Americans at the time had a fear (irrational in hindsight, but rational based on their recent experiences with the Redcoats) of a large standing army as a potential threat to domestic liberty.