I am not a lawyer, and not as smart as many of y'all, but ...
Yeah, if they decide there is an individual right, but the DC gun laws do not infringe upon it, it does leave you wondering what kind of laws would infringe on that right. It might be shrugged off as a "truism" like the increasingly hypothetical "powers...reserved to the States respectively, or to the people" in the 10th amendment.
Calling it an individual right is still a half victory even if they allow DC's restrictive laws to stand. From what I've read, DC argues that they DO allow the right to keep arms because you can own a rifle or shotgun in DC, and use them defensively. No matter how big of a lie that latter is it will be part of the record.
In any case, as an individual right, it can still be brought up in court cases. It means that any law restricting guns will have to go through at least some debate and review before it's passed, and the politicians supporting it will have to explain why they're limiting a right granted in the consitution.
A meager consolation, I agree, but better than nothing.
Because "nothing" is if they review it and say it is a State's right and not an individual right. At that point politicians that are borderline pro-gun no longer have the constitution behind them.
Polls show that most americans, pro-gun or anti-gun, do believe they have a 2nd amendment right to keep and bear arms. If SCOTUS pulls the rug out from under that, will their opinions change? My hope is that Americans will be angry that a right has been snatched away for political reasons, and the result will be a pro-gun movement that actually has some teeth. My fear is that many will just shrug their shoulders and say, "oh, well ... looks like all my teachers were mistaken."
Certainly not for the people on this board, but particularly in blue states I think you'll see a huge change.
And of course we may see some scattered violence. But probably nothing major, as there won't be any immediate impact from a SCOTUS ruling to existing laws. It just opens the door for the anti-gunners to begin ratcheting away our rights in earnest.
If SCOTUS rules it's a weird "state's right," which is an oxymoron if there ever was one, I imagine private gun ownership will be virtually a thing of the past within my children's lifetime.