Didn't the Confederacy have a right to secede?

Lincoln levied war against the southern states, and in article 3, section 3 of the Constitution that makes him a war criminal. Lincoln's war was very unpopular that he launched a war propaganda campaign about American slavery. The Civil War was fought for states rights and limited government, and slavery would have ended anyway. Lincoln prosecuted suspected Confederate sympathizers without trial, and waged an income tax.