According to which law, principle, precedent or past practice?
IbJensen: "Sherman was a deranged animal."
No more "deranged" than Confederate generals who laid waste to Union territories they invaded.
Indeed, far less "deranged" than any WWII leader who directed bombing of enemy civilian targets.
The term for it is "total war", it's been practiced throughout history, and by contrast with mass murders in other wars, Union General Sherman's version was much kinder and gentler.
How can you have a working republic if the national government can arbitrarily lay claim to and assume control of the territory of a State?