Well, a republican put John Roberts in, so don't count your chickens before they're hatched
Roberts is not the problem. In fact, he has been a key advocate of the RKBA.
We were fortunate that 5 Supreme Court Justices in the Heller and McDonald decisions confirmed the Second Amendment as an individual right to armed self defense and must be applied to all levels of government. And, in case you forgot, we were fortunate that Bush, often labeled not pro gun enough, appointed Alito and Roberts as Justices to make that pro-2A majority and obtain those decisions.
However, the minority opinion by the other four progressive Justices was that the Second Amendment: - did not protect a private right of armed self-defense - does not apply to the states - does not apply to individuals outside of the militia context. If there were five, instead of four, anti-Second Amendment Justices the RKBA would have been effectively written out of the Bill of Rights.
It could still happen. The composition of the Court can change and prior decisions can be overturned. The current anti-gun Justices have already stated their intention to do exactly that. Anti-2A Justice Ginsberg has stated that the majority opinions in this case are “grievously mistaken”, that minority opinions would be used to rewrite legal history and create a purely “collective right connected to the militia” and she looks forward to the day a “future, wiser court“ overturns Heller. John Paul Stevens told Time magazine the one thing in particular he would change about the American judicial system “I would change the interpretation of the Second Amendment. The court got that quite wrong.” Stephen Breyer announced on national television his continuing opposition to a real Second Amendment right.
Obama has already appointed fiercely anti-Second Amendment Justices, Sotomayor and Kagan. The next President elect may be able to appoint up to four new Justices. All the anti-2A Justices need is one more “anti” to get a majority of five and implement their stated agenda through the courts.
If that happens we’ll never see a pro-RKBA victory again in our lifetime.