You cannot separate the tariff issue from the slavery issue, they are connected
They were connected in the fact that the North attempted to use the slavery issue to coerce the South into paying the tariffs/taxes and the South used the slavery issue to ‘fire the Southern heart’ when it was thought that the South could not be brought into unanimity about the tariffs. Lincoln’s first Inaugural Address showed his hand. If the South paid the tariffs/taxes they could keep their slaves. According to Lincoln’s own words the horrid institution of slavery was acceptable but not paying ‘taxes’ meant war.