Sbryce,
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
When one leaves emotion and desire out of the discussion, and simply looks at what this amendment says, it is obvious that those who debated and agreed on this wording did so with the intent that the right to keep and bear arms was born from the need to be able to maintain a "well regulated Militia".
Gun rights advocates often argue that the first half of the amendment is irrelevant to the second half. That the "right of the people to keep and bear Arms, shall not be infringed" part can stand alone.
Nonsense.
If those who debated the wording had simply wanted to say that, the amendment would have read more like "The right of the people to keep and bear Arms shall not be infringed." If they weren't expressing the reasoning for why such a right was needed, then why did they preface it with the part about the Militia and security of the state?
The point I tirelessly try to pound into the sometimes seemingly feeble minds of my fellow gun enthusiasts is this: EMBRACE THE FIRST PART OF THE AMENDMENT! The Constitution mandates that a well regulated Militia is necessary. It also says that the people can keep and bear arms to be a part of it. It doesn't matter a rats ass that hardly anyone believes that a "well regulated Militia" is necessary anymore. The Constitution says it is required and that's all that matters. Until the document is amended to repeal the 2nd. amendment, Militia's will be necessary, and the people will have the right to keep and bear arms to be a part of it. It's a means to an end people!!!.......arguing that the 2nd. amendment gives you the right to keep and bear arms, in and of itself, for no stated purpose, is foolish (it's also incorrect). The amendment, in its' entirety, gives you the right. Who cares if it's not for the reason you would like. Be happy! It'll take 2/3 of both houses of Congress and 3/4 of the states to repeal it...it will never happen! By Constitutional requirement, Militia's will ALWAYS be necessary....thus, so will your gun rights.
Whew.....deep breath.
OK, as for "Letters of Marque and Reprisal"....this is a concept that is much older than the United States. "Privateering", as it is more commonly called, was indeed popular in the American Revolution and, to a lesser extent, in the War of 1812. It's swansong, I believe, was during the American Civil War (used by the CSA). Lots of folks getting rich back then, plundering at will with the blessing of our elected leaders (totally acceptable for the time period). I am not aware of any documented instances of privately owned land-based cannon being used in the American Revolution, but I also wouldn't discount the possibility. Anyway....the relevance of such privateering to the wording of the 2nd. amendment is the issue. I say there is none. In the early days, our poor, little Goverment needed all the help it could get. These days, I have a hard time envisioning Congress granting anyone the right to build their own USS Enterprise. Congress alone declares war....don't think they're gonna want our help. Was it on the minds of those who sat around the non-air conditioned chambers where the verbiage of the 2nd. amendment was haggled over? Don't think so. These folks were thinking about standing groups of men, both for homeland security (hmmm...sounds familiar) and for possible foolery undertaken by the boys in Washington. Doesn't really matter what anyone had on their lawn either....the aristocracy of the day were bound by very few laws.
Sbryce - You asked a couple of questions in your post. Does the 2nd. amendment say you can own a cannon? I say no (see above). Someone serving in a Militia, as it was defined in the day of those who wrote the amendment, wouldn't be able to "bear" a cannon. The amendment clearly intended for you to have weapons that you could keep and then bear as a part of a Militia. However, if a cannon existed that you could indeed "bear" (i.e. transport with you without the aid of others or devices), it would be a little less cut and dry. Does it say you can own a shoulder-mounted rocket launcher? Hmmmm....that is a bit tougher. You can keep it and you can bear it. I would have to lean towards the spirit of the amendment being in favor of your "right" to do so. Handguns, rifles, shotguns, machine guns, grenades, small rocket launched weaponry, fully automatic weapons....I believe all of these fit the intention of the amendment and should not be "infringed". Heavy artillery, large bombs, things that couldn't reasonably be carried (i.e. cannon) just don't fit what was intended. If you're hoping for the 2nd. amendment to give you the right to have any weapon of any description in your arsenal...you're not only going to be disappointed, you also have an unrealistic perception of what our common goal should be.
Again, embrace the whole amendment and quit trying to explain away the first half of it. Use it to your advantage. Start liking the word Militia. And, much more importantly, argue from logic and not from emotion and/or unsupportable babble. We'll win much more easily that way. It's the kind of sound reasoning the anti-gunners fear most.
I want to preserve the gun rights that are relevant to 99.9% of us as much as anyone here. I also may understand the game better than most. Use what's there to your advantage. If you do, and take the blinders off, we really can't lose.