Just for one very easy example.. try googling "declaration of secession" for kicks.
And read the words of the CSA leadership themselves,the very men who pushed for secession. Over and over they identify the North as "the anti-slave" states, or the "non-slave" states so many times it is hard to keep count. They identify themselves as the "slave-holding" states, or in phrases as in "our sister slave-holding states" over and over, almost exclusive to any other dewscription of themselves.
The word "taxes" appears just once. The words "cotton" or "tariff" not at all, not once.
http://sunsite.utk.edu/civil-war/reasons.html
The words of the CSA leadership themselves paint the picture very well through their own eyes, and their own words, what the core of the problem was, and the word "slave" and "slavery" show up continously just in these secession documents alone. You might then want to someday read the editorials leading up to secession, or the debates before each state congress voted. If you give me a dime for every mention of the words "slave" or "slavery", or references to their northern enemies as the "non-slave states" and their fellow southern states as the "slave-holding" states, I'll give you ten bucks for every appearance of the words "tariff" or "cotton".
Trust me George, you'll owe me plenty.