Your comment is riddled with errors.
First off, it wasn't "the 3rd year of the war." Lincoln had begun discussing it as early as July, 1862. The Emancipation Proclamation was issued in two phases; the first on 22 September, 1862, and the second on 1 January, 1863. The timing of the preliminary proclamation was governed by the political need for a significant battlefield victory, which occurred at Antietam on 17 September. The war had been going on for quite a bit less than two years.
Moreover, the rationale for the proclamation was not economic as you imply. It was political, and also strategic. There was a significan foreign policy component to it -- in particular, it was aimed at the British and French, who realized that could not recognize the Confederacy without seeming to support slavery (which both had banned).
Third, although the initial Union war aims in the Civil War were not to "fight to free the slaves," the war was nevertheless about slavery. It is nearly impossible to conceive of a Civil War in which slavery was not a factor. The congressional Republicans in the North were always pro-abolition, and pushed hard to gain abolition as a war aim ... and they finally succeeded. The South always saw the Civil War precisely in terms of trying to avoid the abolition of slavery.
Fourth, your comment about Fr. Sumter is simply ridiculous. The issue for Fr. Sumter was resupply: the fort had supplies for perhaps 6 weeks; the South wanted the fort abandoned; Lincoln wanted to resupply it and thereby control the harbor.
“Your comment is riddled with errors.”
Apparently it takes one to know one. Check out this NY Times archived article:
http://www.freerepublic.com/focus/f-chat/2134454/posts
Revisionists have grossly re-written history. They will, and are already doing it to Bush. Many of those who called him a liar believed Clinton’s claim of WMDs in Iraq and the need for regime change even with unilateral military intervention.
It is highly important that we not allow revisionists to do their Orwellian “clean-up” of history.