In December 2024, Japan hosted the United States for the Extended Deterrence Dialogue at the Ministry of Foreign Affairs in Tokyo. Established in 2010, this dialogue serves as a platform for the nations to discuss the extended deterrence strategy that is central to their alliance. The discussions focused on regional security challenges, including Russia’s aggressive nuclear rhetoric and North Korea’s advancing nuclear program.
Both sides reaffirmed their commitment to enhancing extended deterrence, with U.S. nuclear capabilities supported by Japan’s defensive capabilities. The dialogue also emphasized the importance of policy coordination and defense capability alignment to respond to regional threats.
Similar relationships exist globally, with the United States and its Allies relying on each other to ensure security and stability. Extended nuclear deterrence is one of the objectives of U.S. national security and involves extending the umbrella of nuclear protection to Allies to deter attacks from adversaries. This strategy is designed to assure Allies that they will receive the full support of the U.S. arsenal — including its nuclear capabilities. In addition to the nuclear umbrella, the U.S. deploys conventional forces and advanced military capabilities to support an integrated deterrence approach. U.S. extended deterrence committments enhance credibility, provide strategic depth and ensure a collective response to aggression.
The Japan-U.S. extended deterrence alliance has been a pillar of stability in the Indo-Pacific region for decades. With a cooperative relationship dating back to the first security treaty between the two nations in 1951, the U.S. and Japan have continuously strengthened their alliance. The nations have integrated their military technologies and capabilities, ensuring they can respond to threats effectively. Their partnership has contributed significantly to regional stability by deterring aggressors and preventing conflicts.
Japan provides great benefit to the United States as well, hosting U.S. military bases that offer strategic locations for rapid deployment and response. Japan’s proximity to near-peer competitors the People’s Republic of China (PRC) and Russia, provides the U.S. with a critical forward presence to discourage and deter activity that could threaten regional stability.
Extended deterrence alliances such as the one between Japan and the U.S. will become more important in the future. While engaging in diplomatic efforts to promote regional stability and prevent conflicts is crucial, they face several challenges as the global security landscape evolves and adversaries’ technology, tactics and capabilities become more complex. Iran’s nuclear ambitions, the unpredictability of North Korea, the rise of the PRC and the Russian use of aggressive nuclear to enable its invasion of Ukraine, require continuous adaptation of deterrence strategies. Expanding alliance portfolios to better address new missile systems, hypersonics, advances in drone technologies and cyber- and space-based challenges is increasingly necessary and must be addressed through stronger integration between the U.S. and its Allies.
As the global security environment evolves, the U.S. is adapting its strategies to address new challenges, and these alliances play a key role in that effort. By continually evolving and strengthening these relationships, the United States and its Allies can maintain a robust deterrence posture that not only addresses traditional threats but also adapts to emerging challenges.