The Civil War was a war of two economic systems. The Emancipation Proclamation came two years after the succession. This is a history teacher trying hard to be polite...
I have a US History teacher at FSU who would debate you all day long.....
It doesn't change the fact that the US would not bomb Texas back to the stone-age over a peaceful secession. If there was one US state thatc ould successfully secede, my money would be on Texas.