[x]

There are issues that can be peacefully resolved by the political means at hand and those that can't be contained by constitutional politics and provoke violence. Every indication is that the tariff fell into the former category, and the expansion of slavery, ultimately, into the latter. Southerners had secured low tariffs for years, by cooperating with Northern and Western Democrats. They could have continued to do so for years to come. It was Southern insistence on the expansion of slavery that doomed that coalition. Therefore, it's not wrong to argue that slavery was far more important as a cause of the war than the tariff.

[ggekko]

"Therefore, it's not wrong to argue that slavery was far more important as a cause of the war than the tariff...."

You are making a very fine distinction that needs to be clarified. To say that the slavery issue was the proximate cause of the Civil War is, I think, inarguable. To have conceded that point is not the same, however, as saying that Lincoln led the Union into war in order in order to end slavery in the United Sates. It is manifestly obvious that this was not Lincoln's pimrary war aim.

It is my contention that slave-based, Agrarian export-led economies of most of the Confederate states come into intractable conflict with the Empire-minded mercantilist economic system (Clays's "American system") favored by Northern politicians including Lincoln. I don't think unfair to say that Lincoln became, after Clay, the primary exponent of American mercantilism. I would further contend that Lincoln only addressed slavery prior to the Civil War as an issue insofar as it effected the implementation of the American system (high tariffs to protect American manufacturers, government-funded infrastructure development, a National bank).

Across a broad range of issues these two economic systems came into conflict: tariffs on manufactured goods (the Confederates states bought finished good primarily from Europe), non-uniform taxation (many Confderate states paid a disproportionate amount of tariff income into the Treasury which funded infrastructure project sited almost exclusively in the North), the non-enforcement of the Fugitive Slave Act by several Northern states, the establishment of a National Bank (Southern politicians almost universally opposed this measure), and the use of the Dred Scott decision to allow the partial counting of slaves for purposes of Congressional Representation. The extension of slavery into new states was merely a proxy for this broader conflict between incompatible systems.

I don't think that mainstream Lincoln historians have paid sufficient attention to the importance of the macroeconomic consequences of the enforcement of the Morill tariff would have had on Confderate state economies. In Lincoln's innaugural address he did not threaten to use force over the slavery issue but he did threaten to use it to enforce the Morill tariff. The de facto secession by South Carolina in 1828 when they refused to collect the so-called "Tariff of Abominations" was still fresh in Lincoln's mind.

Lincoln kept the abolitionists as part of his coalition and I am sure that he harbored abolitionist sentiments for the most part and particularly after Gettysburg embraced abolitionism more strongly. I believe, however, that Lincoln did guide his policy before the war with the aim of forcing the Confederate states to accept the "American System".