It had been a question begging for an answer since the 1700s.
Most Northern states had made their decisions regarding the disposition of slavery by the mid-1800s under the authority of their own state legislators that led to their own laws.
The South had not adopted their thinking, and that is manifest in the Confederate Constitution. Decades of legislative failure on a national level were finally resolved in a manner to erect a stable system that reduced political sabotage so often seen in the prior sixty years. As Stephens said in 1861, the issue was put to rest. When necessary, the law could be changed by legislation rather than anarchy.
At that time, it was against the logic and wisdom of the period to consider a federal intervention that involved sufficient belligerent force to coerce the peoples of sovereign states to submit to the will of others. It must be remembered that government at that time was very limited and not designed to be involved in the lives of the citizenry other than the few stipulations of the US Constitution. Crusading federal armies riding about to install the laws of one section of states forcibly on other states was a vision beyond the imagination of all but a few that saw the possibility of just that.
Those visionary few have mistakenly become known as "fire eaters". They correctly foresaw that political leaders could and would push aside the Constitution that had been explicitly designed to guarantee the rights of the people as a whole, not of a section.
Here is more on Southern "Fire Eaters".
"Led by such men as Edmund Ruffin, Robert Rhett, Louis T. Wigfall, and William Lowndes Yancey, this group was dubbed "Fire-Eaters" by northerners...
"...They used several recent events for propaganda, among them "Bleeding Kansas" and the Sumner-Brooks Affair to accuse the North of trying to immediately abolish slavery.
Using effective propaganda against 1860 presidential candidate Abraham Lincoln, the Fire-Eaters were able to convince many southerners of this false accusation.
They first targeted South Carolina, which passed an article of secession in December 1860.
"Wigfall, for one, actively encouraged an attack on Fort Sumter to prompt Virginia and other upper Southern States to secede as well.
"Thus, the Fire-Eaters helped to unleash a chain reaction that eventually led to the formation of the Confederate States of America and to the American Civil War.
Their influence waned quickly after the start of major fighting."