This is why it's referred to as The War of Northern Aggression.
The Confederacy didn't do anything much different than when The Founding Fathers seceded from England. The Confederacy didn't attack the northerners, they were attacked. The war was long and bloody because the southerners were defending their homes and families on their own turf.
Tom
Well, there was a bit of a legal question - since there wasn't really anything in the Constitution which said a state
couldn't secede from the Union. The Southern states believed they could secede legally and peacefully - and they also believed they had good justification for doing so. But on a more practical level, they also knew full well that the Union was not going to let them go without a fight.
However, it's not entirely correct to say that the Confederacy didn't attack the Northerners. They did attack Fort Sumter, which is what gave Lincoln justification to call for 150,000 volunteers. He was understandably nervous, since Washington DC is surrounded by Maryland, a slave state, with the Confederacy just across the Potomac River. He suspended the writ of habeas corpus and had a lot of Southern sympathizers locked up. It was a martial law situation. They were rioting in Baltimore, and there was violence in border states like Missouri. It was definitely an explosive situation even before it got started.
They really didn't know what the Confederacy would do, but once they attacked Fort Sumter, all bets were off.
Part of the reason the war was long and bloody was because the Union had trouble finding good generals. Logistically speaking, the North had the South outnumbered and outgunned, plus they had the industry and financial wherewithal for a sustained war. They could have - and should have - won the war much sooner.
By the same token, the Confederates should have seen that they had no chance of winning as early as 1863, after the defeats at Gettysburg and Vicksburg. The Union had control of the Mississippi and the South was cut in two. They were losing in the Western Theater, and the most they could have hoped for in the East was a stalemate. They probably should have surrendered at that point.
And not everyone in the South was in favor of secession. Some were still pro-Union.