You must not read enough of these threads. How often have I read that the was all about oppressing the south? That Lincoln maneuvered the south into firing at Sumter to that he could grab power? Here, in post #111 of this thread, is a typical example: "It was a war of envy, a war to increase federal power (which had it's roots in Jacksonianism) and a war to protect northern industry at the expense of Southern industy."
Then, of course, there's Watie's frequent allusion to the Union soldiers as "the filth that flowed from the north"
The North fought to preserve the Union (and tariffs btw) while the South fought for free and independent states. Slavery was an issue but not the only issue. The quotes and actions of Southerners, including generals and commoners are peppered with pro slavery diction. But if you look long enough you'll also find anti slavers among those dedicated to fighting the North (Lee, Hampton). If slavery was such an issue then those leaders who welcomed the end of it would have been pariahs and such statements would have been blasphemy.
Sorta like me saying "well, Ted Kennedy isn't so bad".