As this book abundantly proves, the abolition of slavery was not among the primary motives of the large majority on the Union side, at least not in 1861-3, before emancipation was promoted as an instrument for defeating the Confederate states.
As Lincoln wrote in 1862:
My paramount object in this struggle is to save the Union, and is not either to save or to destroy slavery. If I could save the Union without freeing any slave I would do it, and if I could save it by freeing all the slaves I would do it; and if I could save it by freeing some and leaving others alone I would also do that. What I do about slavery, and the colored race, I do because I believe it helps to save the Union; and what I forbear, I forbear because I do not believe it would help to save the Union.Again, as the New York Times editorialised even in late 1864:
The Southern masses have been made to believe that the North has been fighting to destroy slavery, to overthrow State rights, and to subjugate and degrade Southern whites. All this is false. The North, though it may destroy slavery in waging war, does not wage war to destroy slavery. There is nothing about slavery that would prevent the North from making peace to-morrow if it could. It is quite willing to leave the whole disposal of that subject to future peaceful and constitutional action. In no form or degree is the adherence of the South to slavery a part of our casus belli.The primary cause of the Union was the Union itself, a cause which embodied an American exceptionalism in which the USA was the hope of the oppressed masses of the Old World. In this idealistic vision, the Civil War was:
really the final contest between free popular government on the one side, and government by an oligarchy or a monarch on the other. (Harper's Weekly editorial, 1863.)In Lincoln's words, the chief purpose of the USA was:
to elevate the condition of men ... to clear the paths of laudable pursuit for all—to afford all, an unfettered start, and a fair chance, in the race of life.The ideologists of the Union side advertised the war as a battle to prove that a free republic built on representative government, free labour, economic opportunity, and religious tolerance could preserve itself.
The question that I find difficult to resolve, is why the preservation of the American Dream, as it were, necessitated the forcible return of the Confederate states to the Union. If the Southern slave-holding, plantocratic culture was inimical to the maintenance of a free republic, then why might the Union not regard itself as well rid of an internal drag on the development of the nation?
I think that trying to resolve this problem brings into view some specific beliefs about the USA and its destiny that might be key to explaining why the Union fought.
Firstly, the idea that the Southerners by maintaining slavery had betrayed founding principles that were as much their inheritance as that of Northerners:
Nor do we fight to subdue or degrade the Southern people. We want them as our fellow-citizens, not as our subjects. We would share equally with them every constitutional right and privilege. We ask nothing inconsistent with honor, or with interest -- nothing but what their fathers and our fathers deemed their greatest advantage and their highest glory.Thus, whatever their differences, Northerners invariably recognised Southerners as co-citizens in a single nation.
Secondly, a sense that the Southern rebellion was not so much an expression of regional diversity of culture and principle, but "the consummation of a social disorder" which "engenders [a] distinct class of 'poor white trash' groveling in hopeless ignorance over beyond the impassable gulf of social class ... In the presence of bonded black labourers ... regarded as a superfluous class..." (Letter quoted in book.)
A Pennsylvania soldier condemned:
a system of labour that gave wealth and luxuriant ease to the few, at the expense of the prosperity and elevation of the masses, and the degradation of labour. (Quoted.)That is, the Southern masses were implicitly identified with by Northerners as oppressed Americans yearning for a free-labour system as the North enjoyed. Thus, the Southern problem was that it had developed a diseased social system that was not so much an authentic expression of sectional culture, as a deviant, un-American aristocracy.
Thirdly, the sociological notion that sectional secession would necessarily presage intra-sectional conflict, and turn the North American continent into something resembling war-wracked Europe:
The North is fighting purely and simply to save the unity of the nation. It has an absolute assurance that this unity is indispensable to the continuance of free and good Government on this continent -- that without it there will be ceaseless conflict, which will be forever exhausting the treasure and draining the blood of both regions until all ends in chaos.Thus, only by forcing the Confederate states to respect the principle of national union could peace and free government be afterwards maintained.
For these reasons, then, to Unionist intellectuals the war was not so much a war against the South, as against an unnatural, inauthentic, un-American, monstrous social system that betrayed the principles and the common white citizens of the South itself. The South was an integral part of the Union that had come to grief by the rise of a tyrannical plantocracy, which Americans North and South ought to abhor. Nor could it be hoped that the Confederacy could eject itself from the Union and then be left by the rump USA to stew in a corner of the continent, since the planter class would inevitably seek to expand its tyranny through both the North and West, bringing permanent war.
If these ideas are right, then the Union fought the Civil War not to abolish slavery, but to defend an idea of a free republic that was essentially not sectional to the Northern states but militantly pan-American. Which raises the question how far this idea of America was a genuine pan-American phenomenon.