A while back, co-blogger Red Emma pointed to a page on Smart Dope, which discussed the question of whether it would have been cheaper to emancipate slaves & compensate their owners in 1860 than to fight the Civil War. Admittedly, the answer to this question isn’t quite straightforward: on the one hand, we can’t be sure how much compensation slaveowners would’ve demanded in such a hypothetical situation; and OTOH we can only guess at how the US economy would’ve fared absent the Civil War. Aside from such uncertainties, however, such a cost comparison raises the question of whether or not the compensated emancipation was even feasible at the time of the Civil War. For several reasons, I’m doubtful that it was.
First, it appears compensated emancipation may not have been politically feasible. By 1860, abolitionists were apparently quite opposed to paying sinners (i.e., slaveowners) not to sin (i.e., own slaves). Even before the advent of this moral stance, however, abolitionist compensated emancipation proposals were repeatedly rejected by antebellum slaveowners, who consistently opposed any proposal that smacked of weakening their “peculiar institution.” Moreover, even if these two interest groups had accepted compensated emancipation, one wonders whether the American people at large would have followed suit. Historically, it took the experience of the Civil War to bring the bulk of northerners around to supporting universal emancipation; and it took enforcement at gunpoint to convince slaveowners to accept that outcome. Absent the war, how likely is it that Americans would have willingly accepted a quadrupling of their tax burden to satisfy slaveowners and a group of radicals?
Economic factors also militated against acceptance of compensated emancipation. Plantation slavery was profitable, and its rate of return was competitive with other antebellum investments. Moreover, slave labor was more efficient than its free counterpart, owing to greater intensity of labor per hour. Finally, given slaves’ adeptness at industrial work, it seems improbable that slaveowners would’ve endorsed compensated emancipation for fear that industrialization might doom slavery. Absent a miraculous mass conversion to abolitionism, it seems unlikely slaveowners would have voted against their pocketbooks.
Finally, the antebellum Constitution erected significant barriers to federal involvement in any emancipation scheme. Enumeration of powers restricted federal interference with slavery in the states. The Fifth Amendment imposed further limits upon any federal emancipation scheme, by requiring Due Process and “just compensation” for any federal taking of private property. A constitutional amendment could have bypassed these restrictions, but for the reasons mentioned above, I don’t think such a provision would have commanded enough political support to win ratification. Nor does it seem likely that the Taney Court – which handed down the Dred Scott decision – would have accepted the sort of creative abolitionist constitutional interpretations proposed by Lysander Spooner and the like. The final alternative would have been enactment of compensated emancipation at the state level; but there appears to have been little antebellum support for such measures in the slave states.
For all the foregoing reasons, I don’t think compensated emancipation was a viable alternative in 1860. One other aspect of the comparison between war and compensated emancipation bears mentioning, however: both sides’ underestimation of the war’s true costs. When “the war came,” both Union & Confederacy thought it would be short & cheap; only gradually did they come to realize that this wasn’t the case. Claudia Goldin – the economist who made the aforementioned cost comparison – suggested as much:
In all probability, the major reason that the war was fought instead of there being a political settlement was that its costs were incorrectly anticipated. The North was obviously surprised by the tenacity of the South, and the South had counted on more support from Great Britain. It appears that neither side thought the war would last more than one or two years.
Or, as the folks at Straight Dope more colorfully observed:
Perhaps had [Southern leaders] foreseen that their society was about to be dismantled with cannonballs they’d have taken the money, said ta-ta to their former chattels, and split for Nicaragua without further fuss.
Perhaps if Alien Space Bats had “Flashforwarded” America’s 1860 population a decade thence, antebellum Americans would have possessed the 20/20 hindsight we now enjoy, and both opposition to war and support for compensated emancipation might have been greater. In reality, however, neither side had sufficient a priori knowledge of the Civil War’s true costs (in both blood & treasure). Hence, we should not be surprised that neither made an accurate comparison of the relative costs & benefits of war vs. compensated emancipation.
Update 20110818: Though I didn’t know it when I posted the above, yesterday Matt Yglesias argued that compensated emancipation would’ve been cheaper than fighting the Civil War. In response, Ta-Nehisi Coates explained why compensated emancipation wasn’t a viable option.
 Claudia Goldin, the economist whose analysis (ahem) figures in the Smart Dope post, considers a compensated emancipation scheme wherein “the government buys slaves from their owners with bonds that pay six percent and are refunded, an equal amount each year, over a period of thirty years.” Claudia Dale Goldin, The Economics of Emancipation, 33 J. Econ. Hist. 66, 74 (1973). Goldin also notes, however, that the “internal rate of return on slave owning” was apparently “ten percent”. Id. at 69 n.5. If slaveowners had demanded this rate, rather than the 6% rate assumed by Goldin, then the price of compensation would’ve increased correspondingly.
 Betty L. Fladeland, Compensated Emancipation: A Rejected Alternative, 42 J. S. Hist. 169, 169 (1976) (acknowledging such opposition).
 Id. at 171-178, 180-182, 185.
 Michael Vorenberg, Final Freedom: The Civil War, The Abolition of Slavery, and the Thirteenth Amendment 38 (paperback ed. 2004) (2001) (noting that “[t]he animosity of northerners towards southern whites, the success of African American soldiers, and the increasing hostility of the [Union] slave states themselves towards slavery – all fueled the drive toward universal emancipation.”).
 In 1860, federal spending was $63,130,598, and revenues were $56,064,608. Bureau of the Census, Historical Statistics of the United States 1789-1945, at 297, 300 (1949). Goldin estimates “the capital value of all slaves in 1860 to have been 2.7 billion 1860 dollars,” and assumes that slaveowners would have been fully compensated for this amount via 6% bonds amortized over 30 years. Goldin, supra note 1, at 74, 75 n.21. The per-year cost of such bonds over 30 years would’ve been $196,152,061.02, or ~3.5 times higher than total federal revenue in 1860.
 Robert William Fogel, Without Consent or Contract: The Rise and Fall of American Slavery 63-64 (reissued paperback ed. 1994) (1989).
 James McPherson, Battle Cry of Freedom: The Civil War Era 97-98 (paperback ed. 2003) (1988).
 Fogel, supra note 6, at 74-75.
 Id. at 78-79.
 Id. at 107.
 See generally Paul Finkelman, Lincoln, Emancipation, and the Limits of Constitutional Change, 2009 Sup. Ct. Rev. 349, 352-355. Note that these limitations did not necessarily apply in times of war or rebellion. Id. at 365-366, 385-386.
 Id. at 352-354.
 Id. at 354-355.
 See generally Randy E. Barnett, Was Slavery Unconstitutional Before the Thirteenth Amendment?: Lysander Spooner’s Theory of Interpretation, 28 Pac. L.J. 977 (1997).
 Fladeland, supra note 2, at 178 (noting opposition to compensated emancipation in Virginia, South Carolina, and “the other states of the Deep South . . . .”).
 McPherson, supra note 7, at 333
 Goldin, supra note 1, at 83.