TL;DR - a proper & updated rephrasing of the right & clause would be "The existence of a standing army notwithstanding, the right of the people to own and carry

TL;DR - a proper & updated rephrasing of the right & clause would be "The existence of a standing army notwithstanding, the right of the people to own and carry weapons shall not be infringed." The typical response equates "the people" with "well regulated militia" by observing that "well regulated" meant equipped & trained, which all able-bodied males were expected to be (per the Militia Act of 1792, each was to buy standardized weapons & gear and participate in local training). The typical dissenting response equates "well regulated militia" to "standing army", explaining the right as "of course active soldiers have a natural right to carry exactly and only what weapons their commanding officers order them to", which hardly constitutes a "right" requiring enumeration. An alternate response I'm growing fond of enhances the "the preamble was explanatory but ultimately meaningless" argument others gave here. The Founding Fathers had a strong dislike for standing armies, but grudgingly realized that one would be required because an armed populace was inadequate to the task of advanced national security. Citizens being an uncooperative & cranky & poor bunch, there would be a need for a well-equipped, highly-trained, severely-disciplined military body ... a standing army, necessary to protect the states individually and the country as a whole; the citizenry should be able to do the job themselves, but we can't be sure without formal troops. Should a standing army be created, they'd be faced with arguments (like we're seeing right now) that there would be no need for an armed population because a standing army was ready to protect the country...and then the government could proceed to disarm the people at large, leaving a situation that the Founding Fathers had just fought a prolonged war to eliminate. Ergo, the right as enumerated is best understood as "The existence of a standing army notwithstanding, the right of the people to own and carry weapons shall not be infringed."