Then you would have to admit that Lincoln was nothing more than some tyrant bent on expanding his empire - no better than Napoleon or Hitler.
Or the United States when they invaded Mexico. With both Grant and Lee fighting side by side against the Mexicans in the invasion of Mexico City.
Robert E. Lee would be a Nazi in your bizarre fulfillment of Godwin's Law.
Is that your argument? If so, wow!
Invasion is a legit excuse for invasion?
A military attack against the United States is a legit excuse for invasion. If the South couldn't hold their own territory, they probably shouldn't have attacked the United States by firing on Ft. Sumter.
Just sayin'.