Secession in and of itself cannot be separated from the justification for it. There may be valid secessions, but in doing so both the reasoning and the methods have to be acceptable.
What bearing do you think this claim has on the what I've taken to calling the "Rainsborough principle", that "every Man that is to live under a Government ought first by his own Consent to put himself under that Government"?
Amadeus would come under the heading of "people who want the most personal liberty and freedom from others", while the Koch Brothers would come under the heading of "people who want to do the most harm to others and prevent the most personal freedom". You say that they "want to get it in the same way", but I don't think that's entirely accurate: Amadeus, at least, take his criticism of the state interventionism to its logical conclusion by opposing the state
as such, while the Kochs and their sort are invariably as enthusiastic proponents of the state as the most ardent Stalinist when it comes to their property. That is no small distinction.
Jefferson suggested rewriting the Constitution every generation or so because he didn't foresee evolution of law under the Constitution as it existed at his time. But the law does evolve with the generations. So each generation is making the government to suit itself. Up to a point, and with conflict in the political process.
A fair point, but the fact that the individual can to a limited extent renegotiate his relationship to the state doesn't mean that it's a fully voluntary relationship. Just because some vague, amorphous "People" or "Nation" can modify constitutional law does not in itself imply that the individual
as an individual is free from coercion.
This is the same old semantics that we cannot find common ground on

What else can I say?
This is a matter of theory, not semantics. You say that people naturally pursue some form of government, and I agree insofar as they pursue some sort of social organisation, but you take to imply in itself a natural tendency towards the formation of States- which for purposes of convenience we can define in Weberian terms, as an entity claiming a monopoly on the legitimate use of force within a given territory- which is far more tenuous a claim. There are plenty of documented instances of people actively rejecting the state, and you could go so far as to say that the entire history of communal-peasant societies consists of trying to keep it at arms length. It's only in certain historical contexts that people find themselves depending on the state, that is, in contexts in which states already exist and in which peoples social being- that is, the means by which they collectively reproduce their society- is irrevocably bound up with them. And, without treading to heavily on all the standard examples (Pennsylvania, 1776; Paris, 1871; Barcelona, 1936, etc.), it's not at all self-evident that the man in the street will march steadily towards the centralised republic rather than simply altering his social being in such a manner as to render the state non-essential.
Not at all. Most conflicts are conflicts of non governmental people and non governmental organizations. The government sets the rules by which these conflicts are resolved. If the government did not do so, then the private sector would be sending men with big sticks to hit the others until the situation was resolved.
There is less actual violence with government than without it.
Well, you're arguing from a comparison between our world and a hypothetical stateless world, but what's the nature of that world? If it's simply one in which every member of the state apparatus spontaenously quite their jobs and went to live as crab fishermen on Fiji, then, yes, you'd probably be right: violence would sky-rocket. But what does that tell us? That the state is necessary
right now? Of course it is- things have been deliberately constructed to make that the case! But that doesn't tell us anything what is possible in the future. By way of analogy, it would be equally accurate to say that the feudal baron was necessary a thousand years ago, and yet nobody today would defend the feudal system, nor were people back then wholly unwilling to challenge the status of the baron, contrived necessity and all.
There may be some successful non violent ways of dispute. But it's rare enough so that it shouldn't be counted on.
My point was that Gandhi didn't pursue his goals through the framework offered to him by the British Empire, but instead challenged the framework itself. Would you say that he was wrong to do so, even though his means were non-violent?