“The states had an absolute right to withdraw from the union”
The Articles of Confederation formed a permanent union of the signatory states.
from Article VI of the Constitution:
“All...engagements entered into, before the adoption of this Constitution...shall be as valid against the United States...as under the confederation.”
It is not a permanent union. The guys who wrote and signed this:
When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature’s God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.
Would not have agreed to a no exit union.
The Framers did not respect the requirements of the Articles of Confederation to the extent of actually obeying them when they called for the Constitutional convention.
The Articles required unanimous consent, which the framers ignored. The Articles required the participation of *ALL* states, but the Framers ignored that.
So if the Framers of the Constitution didn't take the articles seriously, why should anyone?
Yes, and so what? That bound the US, not the states.