Actually it wasn't. But Lincoln did a great job of selling it that way.
IMO anyway.
Bullshit it wasn't. Read the letters of secession lately? The second ****ing sentence of Georgia's letter clearly says it's an issue between Slave holding and non slave holding states. Mississippi? "Our position is thoroughly identified with the institution of slavery-- the greatest material interest of the world. Its labor supplies the product which constitutes by far the largest and most important portions of commerce of the earth." Second and third sentences. Texas and South Carolina's follows those same lines as well.
The war was not fought solely on the basis of Slavery, but it WAS a large part of the war. The States split because they didn't like the Federal Government tampering with their "right" to enslave fellow humans. They claim it was a state rights issue, but it was still about protecting revenues, which is exactly what those slaves provided.
Rebel, you contend that Lincoln "invaded" the south to protect his wallet. Well thats EXACTLY why the South split. You can get all holier then thou all you want about the states rights bullshit, but it was all about money. Them damn Yankees were taking their easy cash flow away, and they didn't like it. So they tried to mask it behind the Constitution, and split because of it. Then they attacked Federal military installations, which as far as any of us who have ever worn the uniform of our nation should be concerned, was a total act of war.
The South fired the first shots. The North just fired the last.