Am just now reading Lincoln and His Generals by T. Harry Williams. He makes this interesting claim: "[Lincoln] soon realized, if he did not know it at the beginning, that the proper objective of his armies was the destruction of the Confederate armies and not the occupation of Southern territory" (p. 7).
This yields two questions:
1. Do we agree with this?
2. If we do agree, how should the victory conditions be modified to reflect it, if at all?
Two other interesting quotes:
"The objective is not to destroy the enemy per say, but to take land. Land that produces supplies and victory points" (from Kyle vs. Keith thread).
"[McClellan's faulty plan] would have made places instead of enemy armies the objective" (T. Harry Williams, p. 31).