I always argue this issue with people. The second amendment of the constitution was originally intended so people could put together militias. Remember, this was when the US was much smaller and had a small standing army. Without the help of the French, we never would have won the revolutionary war.
How the second amendment is interpreted now can be a topic for debate. I think a strict constructionist would agree with me. Loose constructionists would say that the amendment is written with room for interpretation.
That all being said, I am not a lawyer and I'm pulling this from the dusty recesses of my memory of my constitutional law polisci course that I took in college eight years ago.
I am heistiant to address this for fear of hijacking a thread, wich was posted to express sympathy for the victims of what is undeniably a crime. But I think it is deserving of comment, as the issue is obviously linked in the minds of many.
Those who would be called strict constructionists tend to hold the view that the amendment is an individual right. This is because, despite the preface, the amendments plain language gives the right to the people, and not to the states. It doesn't say the right of the state to raise an army, it says the right of the people to keep and bear Arms.
"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."
The concept of "militia" is somewhat misunderstood as well. Proponents of the idea that the 2nd amendment applies to state action, such as a national guard, misinterpert the concept of a militia. The
wikipedia entry for militia, is somewhat enlighting in this area.
A good example are the militias that fought at Concord and Lexington (the opening battles of the Revolution), they where not governement sponsered or in anyway authorized by Britian or the State of Massachusets (the two governing bodies with "authority" over Concord and Lexington). But where rather ordinary citizens who had, had it with the "state".
This is not to say that the ownership of firearms cannot be regulated, and it often is. Try walking down Broadway with shotgun slung over your shoulder. The right to place restrictions on firearms, stems from the preface that the militia be "well regulated". You have the right to own one, but you don't necessarily have the right to parade around town with it.