Assuming citizens successfully re-secure an individual right to armed self-defense subject to strict scrutiny, then a hunt will be on to find a similar stellar candidate to challenge/establish/incorporate the militia clause.
My guess is it will be someone in the reserves (officer rank, Iraq veteran?) who resides in a state where he/she is banned from possessing the very weapon(s) he/she commands in a Nat'l Guard.
Machine guns are too limited - we need to re-establish the concept that the People form the militia and have pre-existing rights to possess sufficient firepower to both help in common defense and/or challenge a potentially tyrannical government.
That would be any a National Guard Soldier in CA, IL, NY or any other state that band the posession of automatic weapons. All M-16's are select fire.