That is an interesting comment.
The power to prevent states from leaving the Union was not delegated to the federal government in the Constitution.
Moreover, when the thirteen united States of America declared independence, it was not by the authority of the Constitution; it was by the authority of the Declaration of Independence.
Unless, or until, the authority of the Declaration of Independence is renounced its consent of the governed theory remains valid.
In fact, the theories in the DOI will remain valid even after all postmodern Hollywood celebrities and their fans renounce them.
Leave the Union via a lawful, legal way, or expect repercussions. Those states that unilaterally left immediately after Lincoln was voted in on Election Day left without even a vote around it. There was no authority to do so within the Constitution, and the Declaration of Independence literally describes the need for “redress” to any issues. When you unilaterally leave your agreement without going through the allowed options for redress (the CSA just abandoned everything, instead), it shows they were cowards and unable to mount any credible verbal fight in Congress or among the States to make changes in a legal manner. It just shows bad faith and cowardice.
I would add that the Declaration of Independence fully allowed a recourse if these normal options were not met through mutually-agreed upon structures:
“We must, therefore, acquiesce in the necessity, which denounces our Separation, and hold them, as we hold the rest of mankind, Enemies in War, in Peace Friends.”
The CSA abandoned the US and became Enemies in War, and lost that war.
So it would appear that, even in conquering the rogue slave-loving CSA, only the United States always followed the Declaration of Rights.
Sucks to be both stupid and wrong, as the CSA leadership was.