Those States have assume the right of deciding upon the propriety of our domestic institutions; and have denied the rights of property established in fifteen of the States and recognized by the Constitution;
Connecting to the fugitive slave act and the Dred Scott decision, South Carolina's injustice shows how opposing people had become. They saw the North's moral opposition to human property as a illegal attack on their way of life.
A geographical line has been drawn across the Union, and all the States north of that line have united in the election of a man to the high office of President of the United States, whose opinions and purposes are hostile to slavery.
Why did the election of Abraham Lincoln feel like a threat to South Carolina even though he promised to not touch slavery where it was already existent? To the South, any political system that treated slavery as temporary, was basically incompatible with their economic survival.
have enacted laws which either nullify the Acts of Congress or render useless any attempt to execute them.
The South did not defy states rights. South Carolina was rather upset that Northern states were exercising their state level authority through personal liberty laws to block proslavery federal rules. They did not want federal restraint, they wanted federal power to be forced onto everyone else.