Not really. It means that the NATIONAL INTEREST that is rooted in the Second Amendment is military....not that the sole purpose is.
If you read the bills of rights of the individual states that pre-dated the Constitution and the subsequent "Bill of Rights", MANY interests are enumerated.
IIRC, Connecticut's version was something like.."the people have the right to bear arms for defense of themselves (self-defense) and their own state (militia service), and the taking of game (hunting)."
The total structure of the federal amendment rules out none of those other uses....it just emphasizes the militia interest as critical to the national interest.
The Military Arms of the day were the same Arms carried by Citizens, Muskets. They matched the Arms carried by the British.
Most of the Cannons used by the Patriots against the British were privately owned. Most of those came from Merchant Ships and were used to defend them from Pirates.
I guess you could say those same Cannons were used for self defense. If you had one it would difficult to conceal. #;^)
I still remember when you could buy a Military Surplus German Anti Tank Gun for $179 from the back of a Magazine.
Well put, WW.