Read through it and try to pull out a central idea that is common to this paper. What appears to you as a running theme in this field of research based on these papers? You can go two routes with this paper. You can focus on something that explains either why countries have pushed away from protectionism or the effects of protectionism. Example focus: “Trade liberalization has been instigated by democratization.” This focus should be a central theme of the main paper you are reviewing.