Did you not read the definition you posted from Wikipedia? "A tariff is a tax on foreign goods." It says nothing about domestic tariffs and foreign tariffs. At any rate a domestic tariff would be unconstitutional, per Article I, Section 9, Clause 5 and 6 wouldn't it?
Ok fine, you were wrong Non-Seq, a tariff IS a tax. Just admit as much.
It's scary when people say things like "a tariff is not a tax" - at least to people like me.
Look, here's the bottom line of the Civil War, what the Civil War was all about. Follow me guys.
1) Lincoln was beholden to Northern Industrialists who were losing business to the South because the South traded predominantly with Europe.
2) Lincoln wanted to empower the federal govt and force his Henry Clay ideas (the American System) on everyone in the country by initiating massive publics works projects in the North.
3) Lincoln had to put massive tariffs on the South in order to fund his American system.
4) The South seceded because of the tariff, not because of some imaginary nonsense that Lincoln was going to war to free slaves in America. The Confederate Constitution is clear on this.
5) Lincoln stated he would collect the tariff revenue by force but was assured the war would only last a couple months.
BOTTOM LINE: This was a tariff war, not a war about slavery.