The Harpers ferry, Dred scott vs sanford, kansas nebraska act, and the election of 1860 contribute to sectionalism in the United States because it led to the situations where people were angry on the issue of slavery and wanted to cause the secession of the the north and the south to be divided.
Sectionalism, not slavery, which only affected a very tiny percentage of southerners, was the primary cause of the American Civil War since it was essential to establishing Southern social life and influencing its political inclinations.
Abolitionists were incensed by the Dred Scott Decision because they believed it would put an end to discussion of slavery in the territories. Slavery-related tensions between the North and South intensified, culminating in the Confederate States of America's founding and the secession of southern states from the Union.
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