So over in R and P there are a couple discussions in regards to secession and the possibility of a second US Civil War. Specifically these discussions center around the unlikely possibility of a US state (or states) leaving the federal Union to become its own nation, as they tried to do once before in 1860/1861. Here's where the mind exercise comes in. Part of the discussion centers around what the possible (if not likely) response would be from the current administration. Now here is where the mind exercise part comes in. One of the lingering questions from the period is who started the fighting, and were they justified in doing so. Of course depending on the author there is going to be bias toward one side, so Im curious to see if the Escapist community can come to a consensus.
The facts: As of the firing on Ft. Sumter on April 12, 1861, there were 10 Confederate states already seceded from the Union (Virginia would join in May), including South Carolina, within whose borders Ft. Sumter lay. Commander of the Federal garrison, Major Anderson, switched his command from nearby Ft Moultrie, which he deemed indefensible, to Sumter, an act which the newly formed Confederate government viewed as hostile intent on the part of the Federal government. Numerous attempts were made to reassure the Confederates that no hostile intent nor action were intended by the United States (including Lincoln's famous "There can be no war without you first starting it"). Despite these reassurances, Lincoln decided to try and resupply the fort, which was low on foodstuffs, with not only more comestibles but also with more troops. The Confederate commander of Charleston harbor (wherein Ft. Sumter was located as protection), PGT Beauregard, upon learning of the planned resupply, decided he could not wait for the garrison to be reinforced, offered Anderson one last chance at surrender, and commenced his bombardment of the fort the next day.
The Confederate argument: All US property within the newly independent Confederate states, including land LEASED to the United States for the erection of forts, armories, etc, was surrendered by the US upon secession of that particular state. Any attempts to retain possession of said property, or to garrison troops within said state, was if not an overt act of war at the very least a hostile invasion of sovereign soil. Combined with Lincoln's intended reinforcement of the garrison at Ft. Sumter, the Confederates saw themselves as under attack by a foreign nation and so acted to defend themselves, as is the right of any independent country.
The US (Federal) argument: Since states did not possess the right to secede from the federal compact, no new nation in fact existed, and as such all states proclaiming to have done so were in fact in open rebellion against the legitimate authority of the whole United States. Therefore, any attempt to impede or hinder the "swift execution of the laws of the United States", including reinforcement of US troops against hostile militia, was a confirmation of this rebellion and as such must be put down in order to restore order.
NOTE: This is a simple academic exercise for individuals with an interest in/ knowledge of the subject.