Nuts, is it? Vague? Have you been paying attention to the SC these last ten years?
What the 2nd means is what the SC says it means. And they have spoken about it in definitive, explicit, straight-forward terms.
They have said, in a nutshell, that the 2nd protects the rights of individual citizens to own and use guns. That that right exists completely independently of any concerns about a militia or of State rights, or of the idea of fighting tyranny. That that right is for modern weapons, not archaic ones. That that right includes semi-automatic pistols, semi-automatic rifles and shotguns used for hunting, and guns useful for home protection.
And the last 3 SC cases use themselves as precedent, as well as use many previous cases as precedent. And there are a ton of previous cases which assert the right of individual citizens to own and use guns. In fact, in the entire history of the US, the right of individual citizens to own and use guns has never been at issue. (What has been at issue is from where those rights originate vis a vis the 2nd Amendment - whether that right is because of State needs, the consequence of militias, etc, and how that would apply to the specifics of the cases that were being tried. And now that discussion is moot) In other words, the last three SC cases are not just explicit, they are based on precedent going back hundreds of years, they are not poorly conceived or argued, they are solid law.
So, whether AR-type weapons can be legally banned under the Constitution - as it is now interpreted by the SC - is the question. As I said, I am not a lawyer, or an expert of the 2nd Amendment case law. But I do know this: AR-type semi-automatic weapons ARE useful for home protection, because they are compact. And they are also extremely popular, which makes banning them way more difficult.
What I want is for every Republican to lose their election. What I want is for The Left to be as effective and as smart as possible at beating Republicans in elections. Trying to ban AR-type weapons, without having a clue whether it is even Constitutional, is not a smart way to win elections.