Let me repeat again that the 2nd Amendment is not about "sporting uses." The arms protected by the 2nd Amendment are first and foremost military-style arms, suitable for use against a tyrannical invader or domestic usurper. That was clearly the theory behind its original enactment. It's unfortunate that Justice Scalia, in writing the opinion in the Heller case, chose to negate the importance of the militia clause. Rightly interpreted (that the militia includes the body of the whole people, not just the organized militia), the militia clause would reinforce the right to own things like machine guns.