From 1960 to 2000, manufacturing supply chains became global. To what extent has this growth in offshore outsourcing and foreign direct investment affected industrial attitudes toward trade liberalization? Using data on public positions of US firms and trade associations on all free trade agreements since 1990, I show that foreign direct investment (FDI) and input sourcing are the primary drivers of support for trade liberalization. Direct import competition and export opportunities play a secondary role in shaping support for free trade agreements. This work therefore adds to the literature on the politics of globalization by providing systematic evidence of a link between global supply chains and industrial preferences, and by developing a new model of the determinants of industrial attitudes toward trade.