Back when the 2nd amendment was written "well regulated" had a completely different meaning than your well educated friend suggest. Well regulated meant in proper working order or functioning well. It had nothing to do with limitations.You know, I've been thinking about this. While I do think I'm fairly well informed about this topic (namely Constitutional issues), I'm by no means an expert. Yes, I've nearly completed a history degree. Yes, I specialize in US history. But realistically, I don't yet specialize in constitutional issues. I primarily focus on the 1830s through Reconstruction.
So I decided to ask an expert. I sent an e-mail to an acquaintance, Dr. Paul Finkelman. Dr. Finkelman is the President William McKinley Distinguished Professor of Law and Public Policy at Albany Law School and a Senior Fellow of the Government Law Center. He's largely considered one of the foremost constitutional scholars in the country. I asked him the following:
Do you think the 2nd Amendment was intended to grant individuals the right to carry concealed firearms? Moreover, do you think the government mandating safety training would be an infringement of 2nd Amendment rights?
His reply: "I have many friends who are hunters, and I love the venison they cook for me. I am an advocate of reasonable and responsible firearms use and regulation. But as a matter of Constitutional law, it seems to me the 2nd Amendment has nothing to do with the right to own private weapons.
The second and third words of the amendment are "well regulated." I think mandatory training, licensing, insurance, registration, and gun cabinets are all constitutional, as are background checks and bans for various kinds of individuals (not only felons). I also think a "ban" on long guns would be stupid and politically impossible and a disaster for the environment. Given the deer population we need more hunters or more wolves! I think there is probably a 9th Amendment to hunt and fish -- all within regulations and rules and seasons."
While his comments are slightly contradictory (if the amendment has nothing to with private ownership, why would "well regulated" apply to such issues) Dr. Finkelman included a copy of his 2006 paper, "A Well Regulated Militia: The Second Amendment in Historical Perspective" which largely clarifies his views. The paper is a solid 30 pages long, so I can't copy it here, but please, read it. The full text is available here. Of particular note is section VIII, regarding the debate surrounding the bill of rights.