I wouldn't say the end result of the Civil War was inevitable. In fact, it teetered on a few battles and events. The Confederates had some supporters across the Atlantic who was more than willing to intervene if they could show they could win some major battles. The Cotton Diplomacy would have also work had England not come out of their cotton shortage when they did. The English needed cotton and willing to bust through the blockade to get it. They were also on the verge of intervening and recognizing the rebels. France was going to follow Britain's lead. Had the cotton shortage been extended, a few more battles won by the Confederacy, the war might have ended differently.
Consider, for example, had Lee's "Lost Orders" hadn't been lost and given to McClellan...