Ahem. It seems to me that the Second Amendment when ratified by the states as part of the Bill of Rights protected exactly the right to keep and own a Brown Bess and "clones," which were undoubtedly "weapons of war."
Unless you think that the Bill of Rights was somehow frozen in time, AR-15 rifles are well within the scope of protected firearms.
And if you don't, how do you feel about restricting the first amendment to hand-placed cold lead type and hand-operated printing presses that produce paper printed materials? In other words, how do you feel about a First Amendment jurisprudence that would not protect any existing newspaper, radio station, television station, or internet site?