With slavery, Lincoln was conciliatory. In his first inaugural address, he said he had no intention of disturbing slavery, and he appealed to all his past speeches to any who may have doubted him. Even if he did, he said, it would be unconstitutional to do so.
But with the tariff it was different. He was not about to back down to the South Carolina tariff nullifiers, as Andrew Jackson had done, and was willing to launch an invasion that would ultimately cost the lives of 620,000 Americans to prove his point. Lincoln’s economic guru, Henry C. Carey, was quite prescient when he wrote to Congressman Justin S. Morrill in mid-1860 that "Nothing less than a dictator is required for making a really good tariff" (p. 614, "Abraham Lincoln and the Tariff").
Lincoln's Tariff War | by Thomas J. DiLorenzo