The 2A says you have the right to bear arms. That can be a wide variety of items, including the bow and arrow, knives, swords, etc...
Should those require insurance, as well?
Not in my view. The problem with guns is partly that so many hundreds of millions of them are out there, with many changing ownership by "underground" means. A system of registration and insurance would, just as it does with cars, ensure that serial numbers are associated with legally-responsible owners, and that transfers and dispositions are documented and take place lawfully.
Your statement is intriguing, though. I've assumed that arms mean firearms. But if arms are more broadly defined, that suggests that a single category of "arms" could be banned entirely and still not infringe on the right. Could guns be banned because folks can always use swords to defend themselves? Obviously that makes little sense in the context of the collective right of defense associated with the "well-regulated militia", but what about in terms of the natural, individual right to self-defense (the one I believe exists, like the right to privacy, in the "penumbras and emanations" of the Constitution but not in the Second Amendment)?
Obviously, Justice Scalia would disagree. Heller involved an effective ban on handguns, and Scalia's concern was that one's natural right to defend person, home and property simply couldn't be effectively exercised without the ability to use a concealable handgun. Knives, swords and baseball bats signed by MLB stars are not effective substitutes.
I don't think the Second Amendment is of much practical utility to the average gunowner - I don't think it is the source of his Constitutional right. I think the Constitution's protection of the natural rights of man - as acknowledged, finally, after two centuries by the SCOTUS - is the source of the right, and creates the limits by which government can restrict and regulate the right.
