Not following your thinking. You contend the Confederates attacked the Union in the Gulf of Tonkin incident, er, I mean the Fort Sumter incident, in order to extend slavery into Federal territories and to continue (I suppose) the violation of free state statutes. How would a Confederate victory have accomplished those things?
One of the first things the Confederacy did after the war started was to invade Federal territory in the Southwest to secure it as slave territory. I assume you must have heard of Mesilla? Confederate forces took it 103 days after Fort Sumter fell, with an expedition that set out less than two weeks after Sumter.
Moreover, the Confederacy in its early days - back when most Confederates believed they had a chance of winning the war and dictating terms to the Union - would likely have demanded the return of fugitive property and contrabands as a condition of a peaceable settlement.
I can't imagine than an independent Confederacy would have signed any treaty that did not compel the Union to return escaped slaves - a grievance that was repeated again and again in secession conventions.
Actually a good question. The Democratic Party split (twice) in 1860 over the South demanding a federal slave code be imposed on territories, regardless of the wishes of the inhabitants.
It seems fairly obvious the CSA, had its secession succeeded, would have demanded some large portion of the territories, with threat of war if not ceded.
They also planned to expand south into the Caribbean and elsewhere in Latin America.
They didn’t think that out either. Given the logistics of the time, the only way such expansion could be supported was by sea.
The US Navy and Royal Navy would have had something to say about seaborne invasions into Mexico, Cuba or Central America.
In general, the South didn’t think thru much about what it would do after secession. They firmly believed slavery would die if it didn’t expand, but they had no realistic way for it to expand. Which meant the logical thing to do would have been to negotiate a gradual emancipation.
But logic was in short supply in the South in 1860/61.