A battle of wills: why the South lost the American Civil War

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Confederate strengths

But Lee’s explanation is too simple. After all, when the war broke out, most seasoned military observers in Europe gave the Union, a government with a tiny standing army, scant chance of militarily subduing the Confederacy, a territory the size of the whole of western Europe. Like their Revolution-era forebears, the Confederates could have won against superior forces because they had compensating advantages: a resilient population, talented military leaders, the advantage of fighting a defensive war in country they knew and, above all, a cause for which most white southerners were prepared to make great sacrifices.

Military observers gave the Union scant chance of subduing the Confederacy

George W Randolph, a Confederate general, expressed a common view in the south when he predicted in 1861 that: “They [the Federates] may overrun our frontier states and plunder our coast, but, as for conquering us, the thing is an impossibility… History offers no instance of a people as numerous as we are, inhabiting a country so extensive as ours, being subjected if true to ourselves.”

If Randolph was right (and Lee was wrong), then the causes of Confederate defeat were internal rather than external. One set of possible internal explanations focuses on political divisions. According to this view, the Confederacy was hindered because its devotion to decentralised government, endless checks on executive power and obsession with individual liberty (for whites) undermined the capacity to fight. Perhaps, in the striking phrase of the late historian David Donald, the South “died of democracy”. Yet what is striking about the Confederacy is how much power the government in Richmond had, taking control of munitions manufacturing, and impounding property. From nothing, the South created what was for a while one of the most effective and disciplined armies the world had seen.

Perhaps, then, the underlying failure of the Confederacy can be found in fault lines in southern society. Did class tensions undermine the war effort? Were women on the home front insufficiently committed to the cause? In fact, only in the final months of conflict did a failure of morale tangibly affect the ability of Confederate armies to resist. This was a tough society.

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The most convincing ‘internal’ factor behind southern defeat was the very institution that prompted secession: slavery. Enslaved people fled to join the Union army, depriving the South of labour and strengthening the North by more than 100,000 soldiers. Even so, slavery was not in itself the cause of defeat. In the end, slavery was destroyed because the North won, rather than the other way around.

If weaknesses in southern society don’t in themselves explain Confederate defeat, does that return us to Lee’s explanation at Appomattox? In a sense it does, but with a crucial caveat: so long as the North remained determined to crush the rebellion by force, it was always likely that its superiority in manpower and resources would tell in the end. But the North had to be prepared to pay the high price of victory.

Morale dimension

The Confederates certainly understood this. The only way the South could win the war was for the North to give up. And so, from the outset, the driving purpose of the military strategy of the South was to undermine northern morale – not just in its armies, but on the home front. That was one reason for Lee’s ‘invasions’ of northern soil in 1862 and 1863. It was also why Lincoln’s re-election was so important, because it represented a continued willingness to fight on the part of the Union.

In the end, perhaps the truth is that the North won the war because the idea of maintaining the Union was powerful enough to overcome setbacks. The North could very well have lost, but only if it had lost the will to win – and, despite occasional wavering, it never did.

Adam IP Smith is professor of US history at University College London (UCL).

This article first appeared in BBC History Magazine's 'American Civil War' special edition