The impact of changes in dominant U.S. threat perception on the cohesion of the U.S.-ROK alliance

Abstract

This thesis starts from the question of what the key factors are shaping the cohesion of the U.S.-ROK alliance. To answer this question, the author researches how cohesion has evolved since the end of the Korean War. Since previous research has focused on the Korean drivers, this thesis examines dominant U.S. threat perception to balance ROK sides. The U.S. has had four significant crises: Detente, the second Cold War, global terrorism, and the rise of China. Following the four crises, this research divides the whole period into four sub-periods. To gauge alliance cohesion, the author chooses four indicators: official statements and documents by leaders, combined exercises and operations, the institutionalization of the alliance, and combined military capability. The results of the analysis suggest that dominant U.S. threat perception determines the strength of alliance cohesion. When the U.S. perception changed, the cohesion of the U.S.-ROK alliance changed in a same direction. The U.S. does not accept ROK’s attitudes – strengthening or weakening – toward this alliance passively, but actively reflects its interests in alliance cohesion.