Reading some history of privateers, I see no indication of any government actually supplying the ships and arms used by them. If the government did supply the ships and arms, then it would be a navy ship and not a privateer.
Ships at sea are subject to attack by pirates such as those around Somalia and they have always been subject to such attacks. It is foolish to operate an unarmed ship in such waters and, in my opinion, the operators of such a ship have an unalienable right to keep and "bear" deck guns of whatever type they see necessary to protect their lives and property. ( The old saying, "Beware of Greeks bearing gifts" refers to a giant wooden horse capable of holding several men and was not something that could be carried by a man.)
If such armed ships are owned by Americans, they have an unalienable right to possess those same arms when in an American port.
Government disarmament is the problem and not the solution.
Once again, did not say such. The letters of marque were their work around to existing situations. The FF's realized that they did not have the weaponry/ships/etc. to shrug off Britain's yoke, so they hired out. Quite common, even today.
Vessels at sea are the odd man out as there were a great majority of privateers. The Continental Congress could not commandeer them, so the basically said, "anything with a Union Jack is fair game, you keep the gold, we get the weapons." But just because they made allowances for such, did not mean that they wanted private ownership of major end items such as frigates and ships of war.
Government disarmament is the problem and not the solution.
Agreed, but I would go even further and say that government is the problem, not just government disarming of the populace.