your view is very jaded.
Here is a quote from 1862 which applies, "The principle [of the Proclamation] is not that a human being cannot justly own another," the London Spectator observed on October 11, 1862, "but that he cannot own him unless he is loyal to the United States" government.
Lincoln had said, "My paramount object in this struggle is to save the Union, and is not either to save or destroy slavery. If I could save the Union without freeing any slave I would do it; and if I could save it by freeing some and leaving others alone I would also do that."
There's much more to why the South left the Union other than slavery. It simply is not that simple.