Thanks Will for responding to my musings about IR's policy relevance. You seem to accept the premise but not the conclusion; so let me respond directly to your objections. I pick on you because your objections are exactly those evident in the broader debate and reflect what I take to be the logical incoherence that generated my initial post.
"If IR research can improve the quality or amount of information that policymakers have at their disposal..."
- This was kind of what traditional area studies did. Scholars spent careers gaining specialized factual knowledge. I think it is the passing of this model that Nye laments and which explains why fewer people jump between academy and government.
- Outsiders cannot have more and better info than insiders. Scholars cannot collect better info (regularly) than that generated by the $47.5 billion we spend on intelligence each year. If it is knowable, and the government cares to know it, government will find it. I think this is the political version of the Efficient Markets Hypothesis. If the government can't find it, scholars sure as hell won't because it's not what we do.
- Boundedly-rational people do not seek more information, biased people are not looking to become unbiased (and don't think they are biased), and problems of incomplete info cannot be resolved because the relevant info is private and cannot be made public (what "type" of nuclear state is Iran?).
- Consequently, if we take our micro theories seriously, then there is no information that scholars can contribute that government is not better placed and more highly motivated to collect itself.
This is exactly the logic that motivates the broader desire for policy influence evident in the wider debate. (Frieden and Lake make a variant of this argument: "Our primary argument is that progress in the study of international politics – including in making its lessons more relevant to policy – depends on more, not less, rigorous theory and more, not less, systematic empirical testing.").
But, the belief that rigor leads to policy relevance rests uneasily (and I think is logically inconsistent) with faith in IR as a social science. We seem to think that we can develop models that accurately explain politicians' choices and then use these models to encourage politicians to adopt policies other than those our models predict they are about to adopt. We seem not to recognize that the better our models explain the choices politicians make, the less they produce policy advice that differs from the policy governments plan to adopt. And if governments are so easily encouraged to adopt different policies, then things are not as systematic as social scientific IR requires.
The simplest of all examples highlights the point. Assume that all that happens in IR can be modeled as variants of a one-shot prisoners' dilemma. So, we have the correct model. Now ask two questions. First, do we think that politicians don't know that "defect" dominates "cooperation" (no; we cannot think this without violating the assumptions that all of IR is a variant of a one-shot PD)? Second, if we tell the government how to maximize its own utility in this one-shot PD, can we give any policy advice other than "defect"? (no, we cannot).
I think people have a vision in which the job of the IR scholar cum policy advisor is to say: "hey, what you need to do is iterate the PD and then play tit-for-tat." What this perspective neglects is that if governments could iterate the game, then they wouldn't be stuck in a bunch of (sub-optimal) one-shot PDs (in which case the one-shot PD wouldn't be the correct model). So, if governments are stuck in one-shot PDs (thus this is the correct model) they lack incentive to change the game, in which case telling them to iterate the game and play tit-for-tat is to tell them to do something they have no incentive to do. You can say it, but governments are not going to find it any more useful than the suggestion that they sacrifice a lamb next time they play.
In short, I fail to see the logical basis for the belief that social scientific IR can provide useful policy advice. In order for our advice to matter, we must make assumptions about politicians that contradict fundamentally the assumptions we make in the models we build. This does not mean we are irrelevant. It means we need to rethink either what we mean by relevance or start talking about the limits of what we can achieve via social scientific IR. We can't continue to pretend that we can have our cake and eat it, too.