Answer :
Final answer:
The Mexican-American War significantly impacted the United States by fueling debates over the expansion of slavery and deepening the divide between Northerners and Southerners, leading to the American Civil War.
Explanation:
The Mexican-American War significantly impacted the United States by raising questions about the expansion of slavery in newly acquired territories like California and New Mexico. This led to heightened tensions between Northerners and Southerners, ultimately deepening the divide over the issue of slavery.
Sectional hostilities mounted as a result of the war, sparking debates and events like the Fugitive Slave Act, Kansas-Nebraska Act, and the Dred Scott decision. These further fueled the discourse on slavery and contributed to the outbreak of the American Civil War.
Key figures like John C. Calhoun and Abraham Lincoln foresaw the implications of the war on slavery, understanding that it would reignite the national debate on this contentious issue and intensify the existing North-South divide.
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