You seem to have real trouble with English.
That clause is not a condition of the 2nd clause. The 2nd amendment discusses two related rights:
1) The right of a State to defend itself.
2) The right of an individual to defend himself (do you know what 'people' means??).
The Supreme Court does not have authority to change or interpret the Constitution. See Article III.
Already been there, done that, and you have offered nothing to invalidate what I posted, and if the SCOTUS didn't have the authority to interpret the Constitution how in the hell does the United States have a military draft? How did Jefferson purchase Louisiana? Why do we have taxes of any kind? How can the Federal Gov't regulate Interstate Commerce? How can anything Congress passes ever be in violation of the Constitution? etc, etc, etc.
Got a feeling I am going to see another copy and paste off of the Google list of fallacies