What was one main issue debated leading up to the Civil War?

The institution of slavery was a central and contentious issue leading up to the Civil War. It was at the heart of the economic, social, and political divisions between the Northern and Southern states. The Southern economy relied heavily on slave labor for the cultivation of cash crops like cotton and tobacco, while many in the North were moving towards industrialization and began to view slavery as morally and ethically wrong.

Debates around slavery included its expansion into new territories and states, with many Northern abolitionists advocating for its restriction or complete abolition. The South, on the other hand, sought to maintain and potentially expand the institution, fearing that losing it would significantly disrupt their way of life and economy.

This conflict over slavery led to significant political strife, including the formation of new political parties, compromises that attempted to balance the power between slave and free states, and ultimately resulted in the secession of Southern states and the start of the Civil War. This issue encapsulated deep-seated differences in American society, making it the most critical factor in the events leading up to the war.