What if the South simply did not take offensive action against Ft. Sumter?
Ft. Sumter was one of only three United States forts located in the states that seceded from the Union still under Union control. In other words, except for those three forts, the South had absolute control of their lands. They had a working government, ship yards, a mint in Louisiana, etc. They were producing their own coinage, had a flag, government, navy, army, and foreign agents that were acting like ambassadors The Confederacy for all purposes, were acting like a nation state.
At the same time, Lincoln was not threatening military action. The U.S. army at that point had only a few thousand solders located mainly in the West, and calling up the state militias was not a popular move. All Lincoln could do is keep the three forts still under U.S. jurisdiction under their control. As long as there wasn’t an attack on the U.S. itself or on U.S. troops, most people in the North didn’t want to bother with the South.
How long would the Confederacy have to be a mere de facto republic before Great Britain and France would decide to recognize them? How would the U.S. put up with the pressure of France and Great Britain before being forced to negotiate with the Confederacy? If the South restrained itself from firing on Ft. Sumter, the North would have never taken action against succession and the North would sooner or later be forced to negotiate with the Confederacy for their independence.
So, why did the South fire upon Ft. Sumter?
One reason is that the South were a bunch of hotheads raring to fight. They didn’t want a peaceful secession. I doubt that even the hottest of hotheads would have risked a war just for the heck of it, though.
Another reason is that the Confederacy at that time only consisted of seven states in the deep South and Texas. The Confederacy’s had attempted to woo the Upper Southern states into joining them, but so far had failed. I doubt the seven state Confederacy was a viable country. If the main ire of the secessionists was the refusal to return run away slaves to their owners, secession certainly wasn’t the route to take. It would have meant that the deep South was now a foreign country. Slave hunters would from these territories would not have permission to roam through the U.S. It is also unlikely that the courts – even in the South would care too much about returning slaves to what is now a foreign government. It would have been impossible to protect slavery in a seven state Confederacy. Sooner or later, the Southern states would have requested to be readmitted to the Union.
Firing on Ft. Sumter and defeating the United States rallied the secessionists in the upper South. It also rallied the North and made it possible for Lincoln to call up volunteers which pushed many states in the upper South into seceding.
Also The Golden Circle fantasy played into the vision of those who worked for the Confederacy. Many of the Filibusterers were Southern proslavery people who later held high office in either the Confederacy or the Confederacy’s military. The Confederate Congress played a lot of games with the idea of invading Mexico, even as late as 1864 when you think they’d have their mind on other more pressing issues. Jefferson Davis also talked about the South being a Tropical Republic.
Slavery was a dying institution when the Civil War happened, and I believe that’s one of the reason it did happen. Slavery was being banned by more countries, and in the U.S., states that use to have slaves had made the practice illegal. The Civil War was the last embers of a dying cause exploding violently before collapsing.