Incorrect in the very first sentence. Five Northern states permitted slavery too, but they didn't have to fight a war.
No, the Civil war was fought to stop independence from Washington D.C. The abolition of slavery was not adopted as a goal of the War until over a year after the war had already been started.
Lincoln was going to allow slavery to continue in the South, so it's hard to argue the war was fought because of the evils of slavery. Apparently it was not considered so evil by Lincoln that he wasn't willing to work a deal to allow it to continue.
People have just been taught history that makes them feel good, as opposed to being taught the unpleasant truth.
They did fight a war you dolt.