Democratic Erosion and Its Implications on U.S.-TURKEY Defense Cooperation

This thesis examines how and to what extent democratic backsliding in Turkey affected bilateral defense cooperation with the United States from 2013 to 2024. It argues that Turkey’s democratic erosion did not produce an immediate rupture in U.S.-Turkey defense relations, but it did weaken the political foundations of the partnership by eroding shared democratic legitimacy and increasing mistrust. Methodologically, the study uses a synthetic control method to estimate how U.S.-Turkey defense cooperation might have developed in the absence of democratic backsliding by drawing on V Dem data, SIPRI arms transfer, and Security Assistance Monitor data. The findings show a divergence between Turkey’s observed defense relationship with the United States and a counterfactual baseline, with the clearest deterioration emerging in the later years of the period. The thesis concludes that democratic backsliding did not solely sever defense cooperation but contributed to the weakening of a critical alliance relationship.