"They have reversed themselves from prior rulings before"Of course, but usually the "holding" is concentrated on the narrowest point of law imaginable....and thus the changes tend to be incremental over a period of time. This pattern changed during the liberalism of the Warren Court in the 1960's when the Civil Rights era was in full swing...and it culminated with the 1972 decision on Roe v Wade. Since that time, the USSC has tended to return to the old "narrow holding" view and thus, slow changes. The crux of the matter this time as you point out is that there is indeed a fair body of prior case law on "point" and it may find itself caught upon the horns of dilemma in that the precedent is over 100 years old...but still binding as are all decisions (those not specifically overturned by legislation or USSC actions) from the High Court.
This is the gray area...the minefield. IF the liberal viewpoint holds sway that the Constitution is a living and therefore evolving document, the 2nd Amendment might be in jeopardy as we know it....OTOH, the strict constructionists will have the powerful voice of tradition in their corner and they will be urging care be taken not to disturb well established case law.
From what I've seen, they overturn a point in a single case, like Brown v Board is said to have overturned Plessy v Ferguson. But all these cases represent a pattern of rulings that form a judicial interpretation of the 2nd.
If they rule that the 2nd is not an acknowledgement of a personal right the bear arms, they overturn all those cases at one time. I think that if the majority are socialist leaning, they, and other socialists in other branches, will work to see that a case that would force them to rule on the constitutional question (Ashwander et al. v Tennesee Valley Authority et al., I think) would never get to them.
We may have already seen an example of that. Ashcroft just recently changed the governments "policy" to one of individual right, which kept (I forget the case, think it was an appeals court in Louisiana I think, restraining order violation) from being appealed.
