Today, as I hinted at in my posting yesterday on antebellum Southern culture, I would like to discuss an intriguing matter involving Abraham Lincoln, slave owner guilt, and the constitutionality of federal regulation of the internal slave trade that was nonetheless never undertaken. The point of this observation will be to demonstrate the corrupting effects of slave owner guilt on the political discourse of the late antebellum South, and its rising inability to deal with the tension between their own moral view of themselves and the immorality of their behavior.
Abraham Lincoln on the Internal Slave Trade
In his famous Peoria speech of 1854, which served as the beginning of the second act of Abraham Lincoln’s political career–opponent of slavery’s expansion and voice of the Northern moral high ground, Lincoln said the following about the Southern view of the humanity of slaves: “Equal justice to the South, it is said, requires us to consent to the extending of slavery to new countries. That is to say, inasmuch as you do not object to my taking my hog to Nebraska, therefore I must not object to you taking your slave. Now, I admit this is perfectly logical, if there is no difference between gos and negroes. But while you thus require me to deny the humanity of the negro, I wish to ask whether you of the south yourselves, have ever been willing to do as much? It is kindly provided that of all of those who come into the world, only a small percentage are natural tyrants. That percentage is no larger in the slave states than in the free. The great majority, south as well as north, have human sympathies, of which they can no more divest themselves than they can of their sensibility to human pain. These sympathies in the bosoms of the southern people, manifest in many ways, their sense of the wrong of slavery, and their consciousness that, after all, there is humanity in the negro. If they deny this, let me address them a few plain questions. In 1820 you joined the north, almost unanimously, in declaring the African slave trade piracy, and in annexing to it the punishment of death. Why did you do this? If you did not feel that it was wrong, why did you join in providing that men should be hung for it? The practice was no more than bringing wild negroes from Africa, to sell them to such as would buy them. But you never thought of hanging men for catching and selling wild horses, wild buffaloes or wild bears.” 
Continuing on in the same speech, Lincoln continues in the same vein speaking of the knowledge of the humanity of the slaves among Southern slave owners and their moral abhorrence of the slave trade on which they were economically dependent, speaking of the slave traders: “If you are obliged to deal with him, you try to get through the job without so much as touching him. It is common with you to join hands with the men you meet; but with the slave dealer you avoid the ceremony–instinctively shrinking from the snaky contact…Now why is this? You do not so treat the man who deals in corn, cattle or tobacco.”  And again (with italics original in source), “How comes this vast amount of property to be running about without owners? We do not see free horses or free cattle running at large. How is this? All these free blacks are the descendants of slaves, or have been slaves themselves, and they would be slaves now, but for something which has operated on their white owners, inducing them, at vast pecuniary sacrifices, to liberate them. What is this something? Is there any mistaking it? In all these cases it is your sense of justice, and human sympathy, continually telling you, that the poor negro has some natural right to himself–that those who deny it, and make mere merchandise of him, deserve kicking, contempt and death.” 
Here we have the first-hand testimony of a witness to the treatment of slave dealers by slave owners from a native-born border Southerner himself, who throughout life maintained friendships with people in his native state of Kentucky. He had witnessed, as a result of visiting the Speeds and other families of his acquaintance, the horrors of the slave trade, and of the South’s guilt in participating in the profitable trade of human flesh, much of it related by blood to the slave owners themselves. Nonetheless, Lincoln wished to show to the Southerners themselves that their discomfort was for moral reasons, and that it demonstrated their own humanity and decency, that they shrank from showing respect and deference to those who made merchandise of their slaves. The tension within slave owners between considering slaves as property and as people was evident, even if unrecognized by the guilty slave owners themselves.
The Importance of the Internal Slave Trade to the South
Let us remember that the internal slave trade was one of the forms of “protectionism” engaged in by the United States after the War of 1812. It is common for neo-Confederates to follow their forebears in decrying the tariffs that prevented the consumers of the South from buying cheaper British imports and forced them to buy Northern goods. The howling of Southerners over the “tariff of abominations” and other laws by which the North protected its own infant industries was loud. However, there were other ways of protecting internal industry that the South profited from, and somewhat hypocritically (and typically) refused to recognize. Among them was the internal slave trade.
How so? As Lincoln stated, in 1820 the Southern and Northern states joined in near unanimity to condemn the African slave trade, the barbaric Western Passage, response for the death of millions of blacks. Now, there are two possible grounds for this condemnation on the part of Southerners. Either they objected to the external slave trade (which, as it happens, they did not reinstate during the Civil War) on moral grounds, or they objected on economic grounds as competition to the slave selling from worn out plantations in border southern areas like Virginia, Maryland, Delaware, and Kentucky to the newer areas of slave plantations like Mississippi, Louisiana, Texas, and Florida. This internal slave trade is what made slavery profitable to those marginal border South slave regions, though it drastically increased the expense of purchasing slaves in the South as a whole. It was, in short, a protected industry of the border South that the South itself supported in order to maintain a larger group of slave states.
To break this down into somewhat simpler terms, the actions of the South in condemning the foreign slave trade and in protecting the internal slave trade were either on moral or economic grounds. If on moral grounds, they were hypocrites for their defenses of blacks as being “naturally slaves” and a lesser type of human. If on economic grounds, they were hypocrites for refusing to show politeness to the slave dealers and in their hauteur shown to Northern industrialists who were concerned more with profits than people. Either way, there is great and profound inconsistency in their conduct, and an awareness of profound guilt that they sought to defensively shove away by defiant defense of their own honor. The fact that their descendants among the neo-Confederates show the same sort of defensive and prickly sense of honor demonstrates that the guilt of slave owners runs very deep indeed.
The Neglected Constitutionality of Regulating the Internal Slave Trade
It is an article of faith among neo-Confederates that the antebellum Southerners who rebelled from the Union had the proper constitutional view concerning the relationship between the states and the federal government and the Constitutional inability of the federal government to enact limitations on slavery. This view is incorrect–for as Abraham Lincoln clearly proved in his Cooper Union address, the signers of the U.S. Constitution clearly saw constitutional limitations on slavery through their own votes to restrict slavery in new territories and outright forbid it in some areas (like the Northwest Purchase–Ohio, Michigan, Illinois, Indiana, Wisconsin, and part of Minnesota). However, in addition to the federal government possessing the sovereignty and mandate to limit slavery was the explicit grant of such power to regulate the interstate slave trade.
This power was granted in the Commerce clause to the U.S. Constitution, which reads that Congress will have the power “to regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes” (Article 8, Clause 3). Interestingly enough, Article 8, Clause 15 of the Constitution gives Congress the right “to provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions,” which meant that the activity of the federal government to crush the Civil War (an “insurrection”) was itself entirely just and proper and within its constitutional bounds .
We might further ask, though, why this undoubted authority of Congress to regulate interstate trade was never used. The reason lies in a paraphrase of John Marshall (and others, “the power to regulate is the power to destroy.” Advocates of the southern internal slave trade understood that if the federal government used its power to regulate the internal slave trade that such trade could be restricted in a way that would make the slave trade a burden to slave supplying regions, mostly in the vulnerable border south, which might jeopardize their commitment to slavery as a way of life, and lead to an erosion of the economic position of slavery by pricing it out of existence. This was clearly abhorrent to a majority of southerners, and so the right of Congress to regulate the slave trade was a dead letter as long as Southerners dominated the Senate and Supreme Court and could ensure friendly (if unconstitutional) decisions like the Dred Scot case. The election of Abraham Lincoln threatened the ability of the South to ensure to protection of its peculiar and immoral institution of slavery, and the resulting insecurity was too much for them to take. It still is.
 Roy P. Basler, ed., The Collected Works of Abraham Lincoln, Volume II, (New Brunswick, NJ: Rutgers University Press, 1953), 264.