The Second Amendment says: A well regulated militia, being necessary to the security of a free state, the right of the people to keep and bear arms, shall not be infringed.
When the Second Amendment was ratified in 1791, the musket was the weapon: the arms. The musket is a singleshot, muzzle-loaded gun. The writers of the amendment did not envision todays assault rifles and the rapid lethal injuries they can sustain.
Arms today could include grenades, military tanks, bombs, bombers, jet fighter aircraft, ships and, for that matter, fertilizer with the potential for bomb-making. Not all are available for the people to keep for use as a weapon.
Assault rifles have no place in civilian lives. If one is a hunter, the hunt is primarily for the sport, the challenge, and not as todays primary family food supply. A hunter does not need an assault rife.
With our democracy and our reputable military, we can be assured that our military will not fire weapons against fellow Americans. If the military would attack its citizens, assault rifles are no match against the available military weapons.
Lastly, ever hear of a drive-by knifing? Could one person with a knife commit a mass murder?