Can a State legally confiscate all guns? Should it be able to?
More generally, does the Bill of Rights bind States, or just the Federal Government?
Even more generally, what does the Fourteenth Amendment mean and how does it bind the States?
IMHO it is "lazy" to assume that this issue is simple or obvious. It isn't.
Rather than get sidetracked by your attempt to obscure the issue (which is the inaccurate postings at freerepublic.com about eminent domain), let me say this about the second amendment.
About 18 years ago, Sarah Brady made my state her pet project. She flew in every other week to wine and dine politicians. I (and a surprisingly small number of others) took my vacation time off one day at a time to lobby my legislator and others to oppose Sarah. We could not wine and dine them and certainly could not get the TV cameras in front of any politician. However, we were able to turn the worst of her proposed laws back. We did not win everything, but I believe we could have it more gunowners showed up like we did.
I heard a number of people at my gun club and at gun shows afterward blowing off about this, that, or another thing to do with the situation shortly afterward. I never saw a single one of them at the legislature when I was there knocking on doors and talking to anyone who would listen. When I confronted some of them, they said they were not there because they had their vacations planned or they had to work overtime or some other stupid excuse. BS. They were just plain lazy.
It is hard to get politicians to do the right thing. If they don't, and you don't do anything, it is your fault. It really is that simple.