Why would it be impossible for the south to win a sustained war with the north?

The South's inability to win a sustained war with the North stemmed from significant disadvantages, including a smaller population and fewer industrial resources, which limited their capacity to produce weapons and supplies. Additionally, the North's extensive rail network and greater financial resources allowed for more efficient troop movement and logistics. The Union's naval blockade further restricted the South's access to trade and reinforcements. Ultimately, these factors made it increasingly difficult for the Confederacy to maintain a prolonged conflict.