The Influence of Rising China on the U.S.–Japan Alliance

The rise of regional powers can shift historical alliances. This article examines the impact of Chinese power on the U.S.–Japan security alliance. Some have argued that China’s rise will strengthen the U.S.–Japan alliance because external balancing will increase as the threat grows. Others argue that, as the potential cost of fighting against China grows, extended deterrence becomes less credible. This article asks the question: is the growth of Chinese power strengthening or weakening the U.S.–Japan alliance? This study introduces statistical tests that suggest China’s rise negatively impacted the U.S.–Japan alliance from 1999 to 2020. To test this, original monthly-level data were obtained from the Japanese Ministry of Defense, including all military exercises. The findings address the geopolitical implications of how the rise of regional powers can affect security alliances between asymmetric powers by increasing the costs of balancing.