Being that I have spent a good amount of time studying the Civil War, I have a lot of discussions with a friend of mine over the reality of a Southern Victory. We normally come to the same conclusion, that the South had no realistic chance of victory. It was near impossible to completely destroy an army during the Civil War. People were looking for the South to get a Saratoga type victory which would force Europeans to recognize Southern Independence. But the importance of the victory at Saratoga was the eventual surrender of the British army.
Even a victory at Gettysburg for the South would not have meant much. George Meade was too good of a general to mismanage the army. Lee and the Army of North Virginia would have been forced back over the border due to a lack of supplies. Vicksburg still would have fallen to Grant’s siege and the war would have continued much as it had. The fall of the Mississippi would have countered anything gained by the Gettysburg victory.
So when discussing a possible Southern Victory in the Civil War it always comes down to Lincoln losing the Election of 1864. Now it’s largely considered that Sherman’s capture of Atlanta gave Honest Abe the momentum he needed to win the Election. But it also helped that Hood had nearly destroyed the Army of Tennessee in pointless counter attacks against a superior opponent. Even worse was the decision to not counter Sherman’s march and instead to take his 30,000 men on a campaign to destroy Sherman’s non-existent supply lines and threaten Kentucky. Sherman’s force was large enough that after detaching 34,000 men under Thomas to deal with Hood, Sherman still had 62,000 men for his march to the sea. Confederates could only raise a total of 13,000 men to counter Sherman, a force that consisted of far too many green troops (along with young boys and elderly men).
So the idea is that if Johnston was never removed from command of the Army of Tennessee, at the very least the lost of Atlanta might have been blunted by Johnston pulling a much larger army out of Atlanta. Johnston also wouldn’t have gone on a campaign into Tennessee/Kentucky on a wild dream. Sherman would have been forced to keep his army together and live or die by a supply line harassed by Nathan Bedford Forrest that extended from Chattanooga. Sherman’s army also had a large number of enlistments coming up.
It would have been possible then for Johnston to eventually force Sherman back out of Georgia. At the very least keeping him from Savannah would have meant he was unable to resupply via the sea like he was in real life. Without destroying the Army Of Tennessee or severely damaging it’s operating ability, it’s possible that Lincoln could have still lost the election of 1864. The election of 1864 is in the middle of the road when it comes to how much of a swing it would have taken for Lincoln to lose.
Although it seems like a longshot, the best shot the South ever had to win the war would probably have been the election. The reality is that the United Kingdom was not interested in helping a slave holding south. The cotton boycott by the South also lead to the UK importing more cotton from India. Although the French did have an interest in Southern Independence (to keep it’s Puppet on the Mexican Throne) Louis Napoleon could not make a move without English support.
Logistically, Industrially and by Population the South was always in a poor position to fight the war. It was an agricultural society in an Industrial age. For example, the South only had a single factory able to produce non-rail steel required to armor Ironclads. They also lacked machine works and the ability to replace damaged machinery. Even the railroad that did exist was a problem. Due to local interference the rail wasn’t a straight run between Atlanta and Richmond. You might have to stop in a small town in North Carolina and board a different train heading north. The reason for the breaks in these lines is because the small towns that sprung up at those towns made a lot of money. Unfortunately due to a lack of engines, men would have to spend 12-24 hours in a small town waiting for the next train. When you consider the importance of arriving on a battlefield in time, these delays were always bad.
The South had the smallest margin of error when it came to winning the war. And as they could never seem to get a capable commander in the west (or at least one that was competent and wouldn’t argue with Davis), along with the leadership drain in the Eastern army (leading from the front lead to higher casualties in Southern Armies) the one advantage the South did have slowly slipped away. Men like Hood found themselves climbing up the ranks in the South not because of anything great they did but simply because they survived. The Civil War is littered with guys promoted above their command, but while the North could always replace such losses, the South couldn’t afford the same manpower losses.