and they couldn't. Though I am not into Naval warfare, I do know some of the militia gunboats consisted of such.
W/all due respect to a heavy student of the period, how can that be? Privateers wouldn't be used much if they didn't get good-sized cannon. Swivel guns would be useless against the Barbary pirates!
What happened - no guns before the letters of Marque, then stocked up thanks to gov permission, do their duty, then get disarmed and gov takes over the "ordnance"?
I'm talking ocean-going ships here, not local coastal militia.
Besides, you said "most" - not all - that means some had big cannon. So it seems moot to imply the 2ndA applied only to small arms.
Or did they just not care at the time if you bought your own real guns?