this thread sparked some interest in what the comparative advantages really were. this is from wiki
Analysis of the Outcome
Could the South have won? The goals were not symmetric. To win independence the South had to convince the North it could not win, but it did not have to invade the North. To restore the Union the North had to conquer vast stretches of territory. In the short run (a matter of months) the two sides were evenly matched. But in the long run (a matter of years) the North had advantages that increasingly came into play, while it prevented the South from gaining diplomatic recognition in Europe.
Both sides had long-term advantages but the Union had more of them. The Union had to control the entire coastline, defeat all the main Confederate armies, seize Richmond, and control most of the population centers. As the occupying force they had to station hundreds of thousands of soldiers to control railroads, supply lines, and major towns and cities. The long-term advantages widely credited by historians to have contributed to the Union's success include:
US economic advantages over CSA
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US economic advantages over CSA
* The more industrialized economy of the North aided in the production of arms, munitions and supplies, as well as finances, and transportation. The graph shows the relative advantage of the USA over the CSA at the start of the war. The advantages widened rapidly during the war, as the Northern economy grew, and Confederate territory shrank and its economy weakened.
* The Union population was 22 million and the South 9 million in 1861; the disparity grew as the Union controlled more and more southern territory with garrisons, and cut off the trans-Mississippi part of the Confederacy.
* The Union at the start controlled over 80% of the shipyards, steamships, river boats, and the Navy. It augmented these by a massive shipbuilding program. This enabled the Union to control the river systems and to blockade the entire southern coastline.[44]
* Excellent railroad links between Union cities allowed for the quick and cheap movement of troops and supplies. Transportation was much slower and more difficult in the South which was unable to augment its much smaller system or repair damage, or even perform routine maintenance.[45]
* Strategically the location of the capital Richmond tied Lee to a highly exposed position at the end of supply lines. (Loss of Richmond, everyone realized, meant loss of the war.)[46]
* The failure to win diplomatic or military support from any foreign powers cut the Confederacy from access to markets. Its King Cotton misperception of the world economy led to bad diplomacy, such as the refusal to ship cotton before the blockade started.[47]