This chapter assesses the book's theory about the effects of intra-industry trade on lobbying in the US case. First, the chapter examines the changing dynamics of trade politics in the United States during the postwar period, and it demonstrates the ways that these dynamics diverge from what is predicted by the classic trade models. Second, the chapter presents testable hypotheses to assess the influence of intra-industry trade on the structure of trade politics coalitions. In the remaining sections, I test my hypotheses and discuss my results and their implications for the politics of international trade. Using firm-level data on trade policy lobbying expenditures for 459 US manufacturing industries, I show that industry associations become less active in their lobbying efforts, relative to individual firms, as intra-industry trade increases. Furthermore, I find that this effect is stronger in import-competing sectors than in strong exporting sectors. This suggests that in import-competing sectors, exporting firms break away from protectionist industry associations to lobby alone for liberalization.