Disclaimer. Don't rely on these old notes in lieu of reading the literature, but they can jog your memory. As a grad student long ago, my peers and I collaborated to write and exchange summaries of political science research. I posted them to a wiki-style website. "Wikisum" is now dead but archived here. I cannot vouch for these notes' accuracy, nor can I say who wrote them.
Kaufman and Pape. 1999. Explaining costly international moral action. International Organization 53 (autumn): 631-668.
If realism is to be believed, states should never undertake "costly moral action"--that is, an international action that brings generally known (and foreseen) costs to a state's material interests or security (roughly speaking). Why, then, do we see state's actually undertake such actions? Clearly realism has a flaw.
The British abolition movement was a costly moral action. When it began, Britain's Indian sugar trade was a major economic sector (and sugar was a slave product). Britain profited greatly from the slave trade. Because Britain stopped trading, importing, and using slaves long before anybody else, it bore both relative and absolute economic costs. Also, it patrolled West Africa and other areas to try to stop the slave trade, costing its navy many lives. This was, by far, the most costly international moral action in modern history.
Realism would argue that moral actions are undertaken only as a cover for something else (e.g. to assert Britain's control of the seas), but it would not allow for any moral action that undermined economic strength or national security (as Britain did). Benefits (in realist terms) were negligible, costs were real, and most Britons were aware of these costs.
Liberal institutionalism explains moral action better than realism, primarily because it shows how international institutions can (a) help other states believe that your actions are not just veiled efforts to boost your own national interests and (b) help prevent free-rider problems in monitoring cooperation. However, since Britain acted unilaterally, liberal institutionalism doesn't help much. Morever, Britain acted against (not with) international norms (especially state sovereignty and freedom of the seas) (pg 640).
Traditionally, constructivism is dominated by two threads. (1) Transnationalism is the idea that state preferences are not necessarily given, but that they can be influenced by crossborder influences. (See Keck and Sikkink especially.) The focus is on transnational advocacy networks and "boomerang effects," with very little (if any) attention given to domestic politics. (2) Cosmopolitanism is the normative idea that we are all equal members of a single human race. Constructivists apply this normative idea positively, arguing that cosmopolitan ethics are more likely to successfully spread transnationally.
Although traditional constructivism should be best suited (of the above) to explain the British action, it fails to do so because it makes two false predictions. (1) Britain should not have opposed slavery until a majority of its population or leaders did so; (2) the moral shift in Britain should have been part of a transnational change, at least among kindred (Western) nations.
The authors identify a handful of primary variables (pages 663-4):
The authors select the British campaign against the slave trade because it is the most extreme example (page 633). But isn't it a bit odd to select a known outlier and attempt to generalize?
Though the authors place their emphasis elsewhere, their own article gives some evidence of rational calculation motivating Britain's action--that is, evidence that Britons may have considered the costs and benefits of their actions. First, for the possible benefits of abolitionism, consider this explanation (at the end of a longwinded section) as to why middle-class white protestants came to oppose slavery:
"Thus for Dissenters opposition to slavery was a way of combating the planters, the oppressive Anglican Establishment, and aristocratically based autocratic rule at home-all of whom supported and were supported by slavery" (647).
Sounds like it was very rational for these people to oppose slavery because it was just another way of opposing their opponents. Did culture/religion really play any role other than reflecting economic/political conflicts (by which I mean that middle-class, political "outs" joined one church, while established groups joined another)? The Torys allowed the Dissenters to join their coalition (and influence their platform) due to domestic political calculations.
Second, for costs of abolitionism, it's possible that abolitionists didn't see abolitionism as imposing great economic and military costs. In fact, they may have perceived the costs of abolitionism as lower than the costs of continued slavery:
"Granville Sharp argued in 1774 that the immoral practices of Britain's autocratic ruling class, including lewdness, adultery, slavery, and other immoralities associated with slave trading, would destroy the entire empire" (648).
The above may seem less than rational because it involves religion and values, yet I can see clear elements of rational economic costs and benefits going into a decision to oppose slavery. The main difference is that one of the most important costs is divine punishment--which is decidedly not purely material.
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