(iPoster) Explaining Variations in the United States’ Responses to Allies' Armaments

• In Event: Poster Session: Security and the Politics of Military Cooperation

Abstract

This paper explains the variations in the United States’ responses to its allies’ armaments, focusing on nuclear weapons, ballistic missiles, and other advanced weapons systems. Despite the United States’ security guarantees and extended deterrence, many allies in the United States’ patron-client relations have sought to develop indigenous strategic capabilities. While previous literature on alliance burden sharing or alliance security dilemma predict either acceptance or opposition to these armaments, this study argues that the patron’s response is contingent upon the perceived effects of the clients’ armament on 1) the patron’s entrapment risk of being drawn into unwanted conflicts and 2) the patron’s control over the client's security policy. When the armament poses little threat to either, the patron generally allows it to proceed (bystanding). However, when the armament is likely to significantly aggravate entrapment risk and weaken the patron’s control over the client, the patron actively opposes or attempts to sabotage it (restraint). Crucially, this study introduces a third category: negotiations. When the armament negatively impacts either entrapment risk or control but not the other, the patron engages in bilateral negotiations to curtail or reorient the client's armament. This research utilizes case studies and process tracing of U.S.-South Korea relations to demonstrate how these factors shaped the United States’ responses to South Korea's missile development. The empirical research shows that the within-case variations in the United States’ perception of South Korea’s missile development substantiate the aforementioned hypothesis. Findings contribute to the field by: 1) developing a new typology of patron responses that moves beyond the dichotomy of acceptance or opposition; 2) providing a more nuanced understanding of the interplay between client armament characteristics and patron perceptions; and 3) offering valuable insights for understanding evolving alliance dynamics in the 21st century, where allies are seeking greater autonomy while navigating complex relationships with the United States. As the incoming Donald Trump administration urges allies to increase their security burden, this research predicts how relations among the allies and the United States will unfold, depending on the trajectory of the allies’ armament efforts.

Authors

• Dabin Lim, Seoul National University

• JH(Jonghyuk) Chung, Seoul National University