Have you read any of the Constitutions of the seceding states?
Have you read the Constitution of the United States and its pro-slavery provisions?
The one unanimously adopted by the slave and erstwhile slave states of New York, New Jersey, New Hampshire, Connecticut, Pennsylvania, Massachusetts, Delaware, Rhode Island and Maryland.
It seems like there were others. Oh yes, the four other original slave states that ended up in the Confederacy: Virginia, North and South Carolina, and Georgia.
Several excerpts.