Tariffs were cited by the seceding states, but subordinate or attendant to slavery. And with the south dominating both Congress and the White House for most of the years preceding the Civil War the best that could be said of it (or the worst against it) was that this was all part of the give & take between states and regions of the country and to say that tariffs were responsible for the insurrection would be tantamount to saying that they rebelled because they didn’t like the drapes.
Slavery, especially in the context of expansion into the territories was at the heart of the souths reason to rebel.
I think you’re thinking may be clouded by years of indoctrination. You have been force-fed “approved” history texts that have confused and twisted the story of our nation and our people.
Slavery was not an ideal institution, but Africa was not an ideal place to live, either. Have you considered how many “slaves” actually came here as volunteers to escape the horrors of Africa? I’ll bet you don’t hear much about that in your mainstream history textbooks, do you?
Try to keep an open mind. Americans are not evil people and Americans never were evil people.