It's not parsing to include the beginning words to the 2nd Amendment.
When there was a frontier, widespread hunting and the need to take up arms as part of a 'well regulated militia', the amendment made more sense.
Do you imagine any of the founding fathers, awakened, cleaned up, fed and made familiar with modern vernacular would not view reports of mass shootings with 'WTF is THAT weapon and why it available to anyone not in the well regulated police or military!?'
Also, 'man we could have mowed down a lot of Redcoats with those; picked up their muskets and sold them with the pitch, never fired and only dropped once.'