I'd agree if we were discussing a bank robbery, kidnapping, or slavery today. But secession was not defined as either thing until after the fact - when the winning side defined it as such.
Today, with just short of half the states in the union currently suing the feds or being sued by them precisely over 21 century interpretations of the Constitution, and with secession creeping back into the debate - it is again a subject for consideration.
How many here who insist that Lee and all his forces were traitors are being called just that today because they oppose Obamacare, bowing to foreign potentates, government by fiat, and a metastasizing deficit?
And...
I wonder how many southerners thought that "the army would never turn its guns on the people" - or on the people's militia??
Not quite correct. It would be more accurate to say that Unionists defined secession as evil from day one and secessionists obviously disagreed. Some still do, as can be seen by many comments in this thread. What was settled by the war was not whether secession was evil, that is something that can still be reasonably debated, but which side of the disagreement would prevail in practical terms.
While in my opinion secession was an evil and stupid policy, I'm not (quite) arrogant enough to classify my opinion as fact.
I wonder how many southerners thought that "the army would never turn its guns on the people" - or on the people's militia??
You should recognize the fact that the initial stages of the war were not "the southern militia" versus the "Federal army," in the sense we might view a similar conflict today.
For all practical purposes, there was no federal army in 1865. The Virginia militia alone had 185 regiments and dramatically outnumbered the federal army of 15,000 men, which was scattered all over the continent anyway. And of course, a disproportionate percentage of the best and brightest leaders of the federal army deserted to fight for the rebels. The conflict in its initial stages was almost entirely between rebel and loyal formations of "the people's militia."
Of course, by the next year the volunteer federal army had become a thoroughly professional force, but then the same was true of the Confederate army.