“Instead it was all about slavery and white supremacy.”
Baloney. Ask the man who waged the war, Lincoln himself.
http://www.history.com/news/5-things-you-may-not-know-about-lincoln-slavery-and-emancipation
His views became clear during an 1858 series of debates with his opponent in the Illinois race for U.S. Senate, Stephen Douglas, who had accused him of supporting “negro equality.” In their fourth debate, at Charleston, Illinois, on September 18, 1858, Lincoln made his position clear. “I will say then that I am not, nor ever have been, in favor of bringing about in any way the social and political equality of the white and black races,” he began, going on to say that he opposed blacks having the right to vote, to serve on juries, to hold office and to intermarry with whites.
Neither was any Southern leader, though I would argue that Lincoln was far more supportive of abolition than they were.
3. Lincoln didn’t believe blacks should have the same rights as whites.
Neither were any Southern leaders.
3. Lincoln thought colonization could resolve the issue of slavery.
So did Thomas Jefferson.
4. Emancipation was a military policy.
Yes, but it was still emancipation. What emancipation policy did Southern leaders advocate?
5. The Emancipation Proclamation didn’t actually free all of the slaves.
No, the 13th Amendment did that. And Lincoln pushed hard to get that ratified and sent to the states.