What was a key issue that led to the outbreak of the Civil War?

The expansion of slavery into new territories was a pivotal issue that contributed to the outbreak of the Civil War. As the United States acquired new lands through events such as the Mexican-American War, debates emerged regarding whether these territories should permit slavery or be free states. This conflict intensified sectional tensions between the Northern states, which were increasingly opposed to the expansion of slavery, and the Southern states, which sought to protect and expand the institution of slavery as a crucial part of their economy and social structure.

The Missouri Compromise, the Compromise of 1850, and the Kansas-Nebraska Act are examples of legislative attempts to address these tensions and avoid conflict, but they ultimately fell short, leading to increased animosity and the eventual secession of Southern states after the election of Abraham Lincoln. This context highlights how the struggle over the status of slavery in new territories was not just a political debate but a deeply moral and economic conflict that ultimately culminated in the Civil War.

Disputes over tariffs, expansion into Canada, and opposition to the War of 1812, while significant issues in their own right, did not have the same direct, immediate impact on the fracture between the North and South that the question of slavery related to new territories did.