The South should have been allowed to leave the Union the same way the colonies left the British empire. You should look at how Robert E. Lee and Stonewall Jackson viewed the decision to secede before throwing out your silly comments. You probably do not know that Robert E. Lee was serving in the U.S. Army when the war broke out and was arrested by the state of Texas.
Both Jackson and Lee were not fond of the decision to secede but felt an allegiance more to the state of Virginia than to the federal government. Add the atrocities committed by Northern forces, for example the intentional targeting of civilians at Fredericksburg, Sherman's March, and even the way Northern troops made sure to bury the dead as close to Lee's wife's home at Arlington to terrorize her and the North can go eff itself.
For what it's worth, I grew up in New England so I'm not some hick southerner clinging on to the confederate flag.
They tried. The difference being they lost their rebellion.