You are simply making up a definition of civil war to fit your opinion on ours. Civil wars can be fought for any number of goals, sometimes limited, sometimes for complete power. But the one factor that makes them civil wars is that they are fought between citizens of the same country.
There are many civil wars all over the globe right now. Name one that is not for control of the government?
The South never called the war a Civil War. That is the term the North labeled the war to try to make it seem like they had a right to invade, subjugate, ravage, occupy and torture the South. Not to mention force them to to stay in a union they no longer wanted. The United States is a compact and soon you will see that many states will be leaving again as the compact is untenable for them as it was in 1861.