The Union army had at least 1 regiment from every Confederate state. That did not work in reverse. Having read all of Kurt Schlichter's recent novels about splitting up, I am not a fan. Everything gets worse and everyone gets poorer.
The land on which "needful buildings" lie (as specified in the Constitution) can be bought back from the feds. The federal government has never had the constitutional authority to hold the vast acres of wilderness that they claim so this is a non-issue. The states can buy the military equipment or let the government reclaim it.
The Soviet Union was a bunch of disparate countries with people speaking different languages who were never one people; there was never parity, never unity. Interestingly, a lot of it stemmed from the loosing of restrictions of the USSR; the people revolted after they gained freedom.
Feel free to explain why you can't have secession while all of that stuff remains largely irrelevant.
How can any contract sidestep the Constitution?
It doesn't really need be a contract. Agree with it or not, there are a number of provisions within the Constitution that have been sidestepped. And while I can't speak specifically on the specifics of land management, traditionally once something has been accepted that contradicts the Constitution, it is rarely changed back. I think you'd have one hell of an issue if you abided, and even participated in something, unconstitutional, and then later, when it benefitted you, tried to have revert it back to the "right" way of doing things.
The states that have been complicit in this have done so because if they reclaim the millions of acres hijacked by the feds they will then have responsibility for their upkeep. Hardly a reason to stand by and do nothing to restore these lands for the use and enjoyment of their citizens.
Exactly, that's why I think it's problematic for them to simply say "this land is ours now." More than likely, they will have to pay something for it, in order to get the feds to relinquish their claim. And that brings up another interesting point. What about money?
They don't have to say "this land is ours now." It never stopped being theirs.
For a lot of the western states where the majority of federal land is, it never was the states' land. The agreement that the land remain federal land was part of the agreements in admitting the new states.
The same federal government that gave back the Panama Canal? Gave back bases in Asia and the Middle East? The same federal government who's capital was occupied by a few dozen unarmed protesters at least one of which was dressed like the village people? That federal government?
