The people of the 19th century would never agree with you.
"The withdrawal of a State from a league has no revolutionary or insurrectionary characteristic. The government of the State remains unchanged as to all internal affairs. It is only its external or confederate relations that are altered. To term this action of a Sovereign a 'rebellion' is a gross abuse of language."
-- Jefferson Davis
Not all of them. Only the ones who were on the wrong side of the war and history.
Not all of them.
"The Constitution of the United States then forms a government not a league; and whether it be formed by compact between the States, or in any other manner, its character is the same....each State having expressly parted with so many power as to constitute, jointly with the other States, a single nation, cannot, from that period, posses any right to secede, because such a secession does not break a league, but destroys the units of a nation; and any injury to that unity is not only a breach which would result from the contravention of a compact, but it is an offence against the whole Union." - Andrew Jackson
The opposing views were debated just as vehemently then as it sometimes still is today.