You are woefully incorrect. The federal government already had authority over arms in the hands of the militia in the original Constitution. Amendment II was demanded in order to make sure that the government understood. That the authority and power delegated to them did NOT extend to arms in the hands of We The People.

   “Also, the conditions and circumstances of the period require a finding that while the stated purpose of the right to arms was to secure a well-regulated militia, the right to self-defense was assumed by the Framers.”–Chief Justice Marshall, U.S. Supreme Court. [As quoted in Nunn v. State, 1 Ga. 243, 251 (1846); State v. Dawson, 272 N.C. 535, 159 S.E.2d 1, 9 (1968).]