A civil war is a contest for government control of a specific country. The English had a civil war, back in the 1600s with the Roundheads and Oliver Cromwell. Spain had a civil war right before WWII. China had a civil war between Mao and Chiang Kai-Shek, resulting in the twin states of the People’s Republic of China and the Republic of China.
The Book of Mormon has an account of a civil war, found in Alma 2. Note that both sides were fighting for control of the same country.
In the case of the US “Civil War,” however, there was not a struggle for control of one government, as in other civil wars. The South (the Confederate States of America) wanted to preserve their way of life and freedoms by starting their own country, independent of the Union up north. One can imagine ways (other than the Civil War) which would have lead to peaceful coexistence of the two countries.
One of the great complications is that once the Confederate States of America declared independence from the Union, the Union still had military bases in the South, like Fort Sumter. The prudent thing to do, the way to avoid a war, would have been to pull out of military bases. If, as John Locke insisted, people have the right to consent to their government (and to throw it off if it becomes tyrannical); and if, as the Framer’s insisted, there was a co-legitimacy between state and federal governments; and if, as the ninth and tenth Bill of Rights indicate, the powers of the federal government are limited to that expressly found in the Constitution, then once the Confederate States of America declared independence, the Union bases there were essentially unwelcome occupying forces. Remove the occupying force and make peace!
But, of course, that’s not what happened. And I don’t think the South was completely blameless, either.
The US Civil War was fought over whether the South had a right to govern itself as an independent country, the Confederate States of America. They saw their struggle as one to preserve their freedoms and their way of life. The North saw the Union as indivisible (or so the textbooks tell us), and thus, the Confederate secession was an act of rebellion, of war. Dissolution of the Union was an impossibility!
This, of course, flies in the face of John Locke and the American Revolution itself. Dissolution is only impossible as long as the people consent to the union. Once the consent is lost, the bonds between man and government, in Locke’s view, are justified in being severed. Unfortunately, the North didn’t see things this way.
Why is this not a civil war? The South was fighting for control of their own land, not control over the North. There was no wrestling for control of the Union government. It was, rather, a War Between the States, a war to determine whether the Southern government would stand. In the eyes of many southerners, it was (and to some still is) the War of Northern Aggression, as the South felt they were defending their way of life against the centralized encroachments of the North.
Many historians and critics at the time (in the North and in Europe) saw this as a power grab, where the Union wanted to exert a dominant and even imperialistic influence over the South. Unfortunately, this alternate perspective is all but lost in today’s public schools, where unquestioned veneration of Abraham Lincoln and unquestioned support of the Civil War seems the rule. And so a change in popular perspective is unlikely, at least for the time being.