This won't work. The machine gun is clearly of a type which is useful to a militia. Suggesting that one may disarm the militia because criminals might find firearms useful is ridiculous and certainly not a narrow limitation, given that virtually every soldier is trained and equipped with such a firearm.
Furthermore, the limitations on machineguns are written as tax laws granting the government the power to refuse to accept the tax. That is ridiculous treatment of a Constitutional right. There are some interesting decisions ahead.
I agree. I really hope that SCOTUS ignores the briefs and hears the cases. First and formost the GCA and the Firearm Owners Protection act of 1986 are unconstitutional. True, gov't can tax machine guns but they cannot prevent ownership of newly mfr'd weapons as they have done since 1986. They can require certain safeguards for the general protection of society but they cannot legally prevent ownership. SCOTUS has ruled this in past cases. This is merely a minor victory in an attempt to please both sides of the argument. Should SCOTUS accept both cases & rule in favor, the Feds would have some real logistic problems on their hands, (and I'd have me a new H&K MP5 ;)