From Vox EU:
Offshoring and unskilled labour demand: Evidence that trade matters, by Juan Carluccio, Alejandro Cuñat, Harald Fadinger, and Christian Fons-Rosen: ... Conclusions The empirical evidence suggesting that globalisation is indeed affecting the income distribution in industrialised countries is much stronger than initially thought, at least as far as the manufacturing industry is concerned. In fact, the productivity gains from having access to cheaper inputs through offshoring are not being distributed equally between different economic actors in our rich societies. Consequently, political resistance to free trade by certain groups has a clear rationale as long as the effects discussed above are not addressed through more effective redistribution policies.