I haven't had the time to read anything other than second-hand commentary on the WikiLeaks document dump, but as "revelations" go, this one seems to be weak tea. The direct effect on the Afghanistan War will most likely be felt in some of the relationships the U.S. must manage (Pakistan and India, for instance).
There's also the risk that some of the granular information they contain, which extend to some NATO coalition partners, could accelerate the crumbling of support in Europe.
Beyond that,
as Joshua Foust noted, there is the human cost faced by Afghan informants and other strategic assets whose identities have been compromised, and the systemic risk of the intelligence community viewing information-sharing with an even warier eye.
More than anything, though, the documents serve as yet another reminder that war requires secrecy, which by definition means hiding the truth. Sometimes that truth is hidden by government classification, while at others it is simply obscured by an overwhelming mass of data points and information overload.
For obvious reasons, such secrecy over the long term is incompatible with democracy. That is why democracies face a double disadvantage when engaging in war. Not only do they have to maintain popular support for the duration of the war effort, they also put at risk -- and at times actively undermine -- their own foundations by engaging in that war effort.
The danger, however, arises when secrecy crosses over the line into deception. And by this measure, the WikiLeaks documents, if anything, reassure. They "reveal" not only what most open source news outlets have thoroughly covered, but also what the U.S. government and military has largely admitted. If the documents themselves were protected by the shroud of classification (in part because of the cost of vetting such a mass of material for declassification), the picture they paint has already emerged from other sources -- both private and public, on and off the record.
If most Americans are not sufficiently aware of that, it is in part due to the information overload they are faced with, and in part due to their own choices of news consumption. Both causes reflect broader imperfections in our political system whose impact is not limited to the Afghanistan War.
Either way, however, the WikiLeaks documents suggest that, for now, at least, America has withstood the toxic effect of secrecy and war on its democratic institutions. And for that reason alone, the benefits of their release seem to be overshadowed by the costs.
