Drivers of Nuclear Arms Control Outcomes : Treaty Design, Status, and Structural Domestic Politics in the Russia–U.S. Context

Sammanfattning

Recent years have seen the gradual disintegration of the Cold War bilateral nuclear arms control framework. Arms control faces multiple challenges, including emerging technologies, the rise of additional nuclear states and increasing complexity in multilateral nuclear dynamics. As the last bilateral nuclear arms control treaty between Russia and the United States is set to expire in February 2026, understanding the factors behind the success and failure of past treaties offers valuable insights for future bilateral arms control efforts. This thesis examines the role of three factors in shaping the outcomes of three bilateral nuclear arms control treaties between Russia and the United States: START II (1993), SORT (2002) and New START (2010). Using a mixed-methods approach combining deductive coding, thematic analysis and process tracing, it explores the influence of treaty design, particularly monitoring and verification mechanisms and irreversibility, status aspirations and structural domestic politics on success and failure in commitment, implementation and treaty durability. This study argues for a synthetic approach that considers the interplay of treaty design, ideational factors and domestic political structures in understanding nuclear arms control outcomes. Results indicate that monitoring and verification mechanisms, irreversibility, status aspirations and structural domestic politics can support successful treaty outcomes, though their effectiveness depends on political will and the broader strategic context. Status aspirations play a dual role, at times facilitating cooperation, while obstructing treaty processes under certain conditions. Lower levels of irreversibility can weaken treaty outcomes by making commitments easier to reverse. The influence of structural domestic politics appears largely confined to the ratification stage, either aiding or hindering treaty approval.