For those who are interested, I just published a post on state's rights on my Civil War Blog. You can see other posts on the causes of the Civil War here.
As we have discussed on this blog before, slavery was the main issue that caused the Deep South States to secede, but secession did not necessarily mean war. This is a major misunderstanding about the Civil War today. When the North was considering whether or not to attack the South, the question was no longer about slavery. The question was whether or not the Southern states had a right to be allowed to leave the Union peacefully. The South viewed the United States as a confederation in which the states joined together for mutual protection. They joined freely, so they thought they could leave freely. However, the North believed that the states surrendered their sovereignty and could never regain it. It was this difference of understanding that caused the South to fight for freedom and the North to preserve the indissolvable Union.