I agree. However the main issue through the first thee years of the war was 'The Union' with slavery being the catalyst that brought it forth. Yes, in time through the efforts of the abolitionists and the horror of a grinding Civil War, the people of the North recognized that slavery had to die, now. Piecemeal wasn't going to suffice. Thus the Emancipation Proclamation, which 'freed the slaves' only in the Confederate States. It was the principle.