With strong advocacy by Antonin Scalia, the Supreme Court has essentially eliminated the first four words from the Second Amendment. So in practice the meaning is exactly what the NRA wants it to be — “Being necessary to the security of a free State, the right of the people to keep and bear Arms shall not be infringed.”
Scalia was all about “original intent” in the Constitution, and yet regarding the Second Amendment he insisted upon a radical reinterpretation. One of the four justices dissenting against Scalia was John Paul Stevens. Now retired, Stevens has proposed this amended wording to clarify the original meaning of 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 — when serving in the Militia — shall not be infringed.”