The End of Slavery and the Reconstruction Amendments
The Constitution provided a process for states to enter the union, but had nothing to say about what would happen if a state wanted to leave. The tensions that had been temporarily calmed after the Nullification Crisis continued to rise. As President Jackson had predicted, slavery was put forth as a main cause of the conflict. And it was indeed the main cause. While Lincoln had believed it was “in the course of ultimate extinction”, slavery was not going to just go away.
The interests of Northern and Southern states grew increasingly divergent. As more states joined the United States, tensions about the balance of power between slave states and free states reached a tipping point. Southerners feared that Congress would try to ban slavery where it already existed, while Northerners feared the “slave power” in Congress and resented the injustice of federal laws that required people in free states to return escaped slaves to the their masters.