The correct answer is "By igniting debate over the expansion of slavery."
Every time the US wanted to add another state to our country, the issue of slavery would inevitable come up. This caused a huge division between Northerners and Southerners. Congress tried to compromise on this issue several times by making laws like the Missouri Compromise, Compromise of 1850, and the Kansas-Nebraska Act. However, these all failed at solving the issue and only lead to more tension between the North and South.
well many people thought the us should not enter the war because the us had a lot of problems during that period. hope this helps let me know if im wrong
