I think Mr. Delmore has absolutely hit the nail on the head about original intent and the Second Amendment.
When the founding fathers wrote the Constitution and following amendments, America was a young, new nation. There were no police forces, sheriff's departments or military services as are constituted today. Not only did the average citizen need a weapon to possibly have to protect his family from our Native Americans, but also the British as in the Revolutionary War and from fellow citizens with criminal intent. Not to mention the fact that unless one wanted to be a vegetarian, a weapon was needed for hunting wild game. The country was not covered with herds of cattle then, just the bison out West that were slaughtered for their hides.
I doubt the founding fathers ever imagined the evolution of the flintlock to the AR-15 and AR-16 that sick people are now able to use to commit mass carnage on their fellow human beings. To try to remove these weapons from the American public could now result in much more blood being spilled on American soil by their fellow Americans. The great majority of gun owners are sane, responsible, law-abiding people. The challenge lies in identifying those who are not and the rest of us having the will to do something about it.