Assessing the influence of the United States' nuclear deterrent on the China-Japan security relationship

Abstract

To what extent has the United States' guaranteed nuclear deterrent to Japan influenced the security relationship between China and Japan? The conventional wisdom holds that while the overall balance of U.S. influence has been to both ameliorate and exacerbate tensions between Tokyo and Beijing, Washington's nuclear guarantees in particular have served to reduce tensions by helping to prevent a nuclear-armed Japan. Much scholarly work has been dedicated to analyzing the U.S. impact on the China-Japan relationship generally and the prediction of increased tensions resulting from changes to the U.S. nuclear umbrella (namely, development of ballistic missile defense). However, little attention has been paid to assessing how the magnitude and direction of U.S. influence have varied over time and whether the predictions of a worsening Sino-Japanese security dilemma have come to fruition. Conducting a historical analysis of the period 1945-present, this thesis finds that the influence of U.S. extended deterrence is more nuanced. While the strongest influence has been to ameliorate long-term hostilities, the influence most frequently felt was exacerbation of short-term tensions. This influence notwithstanding, this thesis finds that changes in the U.S. nuclear guarantee to Japan have infrequently been associated with changes in the China-Japan security relationship.