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Original Intent and Purpose of the Second Amendment
Introduction
The Second Amendment:

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.
The original intent and purpose of the Second Amendment was to preserve and guarantee, not grant, the pre-existing right of individuals to keep and bear arms. Although the amendment emphasizes the need for a militia, membership in any militia, let alone a well-regulated one, was not intended to be a prerequisite for exercising the right to keep arms.

The Second Amendment was meant to preserve and guarantee an individual right for a collective purpose. That does not transform the right into a “collective right.” The militia clause was a declaration of purpose, and preserving the people’s right to keep and bear arms was the method the framers chose to, in-part, ensure the continuation of a well-regulated militia.

There is no contrary evidence from the writings of the Founding Fathers, early American legal commentators, or pre-twentieth century Supreme Court decisions, indicating that the Second Amendment was intended to apply solely to members of an active militia.