If this court rules that the 2nd is an individual right, and an earlier court ruled (erroneously perhaps) a sawed off shotgun not protected because it wasn't a weapon commonly used by the military, can we infer that individuals will have the right protected by the constitution to bear weapons commonly in use by the military?
That is a very good question. Toad could answer this better than I.
My opinion is not worth much but from reading a little, it seems the NFA (National Firearms Act) of 1934 was in response to public outcry over the St. Valentine's Day Massacre. It was required to register certain short barreled and automatic firearms with the MTU (Miscellaneous Tax Unit), later to be called the BATF. Back in those days, the $200 tax/fee was a prohibitive measure designed to restrict ownership of these style weapons. $200 was a lot of money compared to what a firearm would cost.
The Miller case (erroneously) determined short barreled shotguns were not military weapons, and the case was based largely on what weaponry defined "efficiency" in a militia, i.e. weaponry commonly used by the military. The Supreme Court determined SBS's were not military weapons.
In the Supreme Court hearing of the Miller case, the defendants did not show up in court because Miller had been killed and Layton (the other defendant) took a plea bargain before any defense could be formed. This case resulted from Treasury agents looking for a moonshine still and finding one which was non-functional and hadn't been in operation for awhile. They did find Miller's sawed off shotgun on the seat of his truck, and made an arrest on that to save embarrassment from not finding an operating still. Miller had not paid the MTU tax on his firearm.
The U.S. Western District Court for the Western District of Arkansas originally ruled the NFA violated the Second Amendment. The SC reversed that ruling based on what defined a military firearm suitable for a militia. The SC also remanded the case back to district court for further proceedings, which never took place due to no defendants present. A defense was never formed and the Miller case was not completely decisive.
To me, it sure does infer that if the Second Amendment is interpreted as an individual right guaranteeing a right to bear arms (commonly in use by the military,) small arms such as short barreled shotguns and mgs would no longer require taxes/licenses to possess and would basically fall under the same category as handguns. I believe a small arm is defined as any (loaded) firearm which can be carried easily by one person. It does not include ordnance.
The original prohibitive nature of the 1934 NFA was due to gangster usage of certain firearms as SBS's and fully automatic weapons. It's hard to imagine any of the restrictions on those firearms changing because of a constitutional ruling. The original NFA was created by public outcry and unconstitutional according to District Court, yet it has stood up to this day. It's my understanding the Miller case wasn't handled in a completely decisive manner by the SC. Gun control groups champion it as a precedent ruling. We can hope an individual right ruling would pave the way for easing restrictions concerning handguns and concealed carry in all 50 states and Washington DC. I doubt regulations and laws concerning sawed off shotguns and such will change, but theoretically those laws could be relaxed you'd think.
So, to answer your question Iron, in my opinion yes it could be inferred but I don't think it'll happen.
Les