I have been struggling over a paper on distributive justice and international law, for a conference April 7 at Cornell. This seems an example of failure of comparative advantage (why should I try to learn philosophy?), but it also occurs to me that the distributive justice issues cannot be answered by philosophers alone, because they require lots of practical (legal) and empirical (economic) inputs. Fernando Teson has an interesting post on this at profsblawg. The development economics of international trade is a bit of a moving target (literally, as one group, led by Rodrik, suggests it depends on the particular moment in the relevant state's economic development), although Teson has grasped on the Bhagwati view that liberalization pretty unambiguously promotes development. I am also working on editing Hudec's 1987 book on developing countries and the GATT, and Hudec had a nice way of squaring the circle despite disagreement within the economics profession or among policymakers.
The philosophers I have read on this subject, including Rawls, Walzer, Pogge, Singer, Beitz, and several others, seem to have a mixed understanding of the role of the WTO, basic trade economics, basic development economics, etc. Rawls, writing in The Law of Peoples in 1999, referred to the GATT as the global trade organization. I must confess to a mixed understanding, also, but my mix is somewhat different from theirs. Teson's complaint calls for more interdisciplinarity, and here one can only agree.