No, that was already covered in the militia clauses of the original body of the Constitution. Congress was given the power to provide for arming the militia and for providing "discipline" (which meant the drill manuals and such). They were also given the power to make the rules for governing that part of the militia called into actual federal service. The President is commander in chief of that portion of the militia called in to actual service, and the Supreme Court has jurisdicition over matters involving the militia, when in actual federal service.
The Second Amendment was to ensure that the militia could be armed, even if Congress and/or the States failled to arm them. In the "pre-amble" of the second amendment, "A well regulated militia being necessary to the security of a FREE state" (emphasis added). the operative word is "FREE". (by state they did not only mean one of the several States, but a government in general.)
Furthermore they not only wanted to ensure that the militia would be armed "Just in case" of insurrection or foreign invasion, but to prevent the government from disarming the milita for it's own, that is the government's, "security", should it overstep its Constitutional bounds.