Slavery is an affront to the unalienable rights of some and to the freedom of all.
The southern separatists were no less legitimate than the colonial revolutionaries who overthrew the British government.
The colonial separatists fought for a higher degree of freedom. The southern separatists did not. You can't have a higher degree of freedom when one of the primary things you are fighting for is to protect slavery.
You bet the colonial separatists were more legitimate.
If this were the reason why the Union wanted to outlaw slavery, then you'd have a point. And if this statement were true, then the Union had no business allowing it in the first place. Abraham Lincoln even stated that the basis of Civil War was the preservation of the Union, not the elimination of slavery.
The colonial separatists fought for a higher degree of freedom. The southern separatists did not. You can't have a higher degree of freedom when one of the primary things you are fighting for is to protect slavery. You bet the colonial separatists were more legitimate.
For all intents and purposes, the United States as the colonial separatists envisioned it no longer existed by the time 1860 rolled around. I have often made the case that the United States really only lasted a few years -- until the events that culminated in the Whiskey Rebellion in the early 1790s made it clear that the U.S. government was really not all that much different than the British crown.