Author: Daniel Gearin, Center for a New American Security

We live in a world today with fewer nuclear weapons than in the past, but more states are in possession of them. In this context, the United States has adopted a policy that de-emphasizes nuclear weapons, which has raised questions about whether the United States maintains its deterrence capability. These developments are all taking place in a messier world and Japan is responding to these changes in a variety of ways. Takahashi Sugio highlighted changes in Japan`s National Defense Program Guideline (NDPG) as examples of the Japanese response. Sugio also noted that Japan is concerned with two challenges in the realm of nuclear deterrence; the deterrence of actual use of nuclear weapons, and how a changing nuclear balance can influence the behavior of regional powers. For Japan, the latter challenge is more important than the former for deterrence policy.

Japan`s perception of the issue of assurance continues to rely on the United States. In order for Japan to be properly assured, the U.S. declaratory policy which explicitly extends its nuclear weapon over Japan goes a long way. The United States has repeatedly reiterated its defense commitments to Japan after security incidents have occurred in the region, which further reconfirms Japan`s feelings of reassurance. Clearly deterrence and assurance are closely linked for Japan. Martin Fackler spoke to this point in that there is little public debate in Japan regarding acquiring nuclear weapons, which is largely due to the fact that they maintain feelings of assurance from the United States. This reliance on the U.S. nuclear umbrella to provide for Japanese feelings of assurance will continue into the future for as long as the United States maintains forces in Japan.

Victoria Tuke highlighted the differing perceptions of deterrence that exist between Washington and Tokyo. In the post-Cold War, the United States views terrorism as the greatest threat to its national security, along with a variety of other non-traditional security threats such as cyber-attacks, piracy, etc. Meanwhile, Japan continues to view state actors as the primary source of security threats. These differing threat perceptions invariably influence how the respective countries view the applicability and utility of nuclear weapons for deterrence today.

Despite the fact that U.S. commitment to Japan is unlikely to change in the short term, there are a number of changes taking place in Japan’s external environment that are troubling for its security situation. North Korea has long served as a source of insecurity for Japan in the region, but the rise of China is increasingly becoming a cause of concern for defense officials in Japan. These changes are causing some anxiety in Japan over the future of U.S. commitments. Meanwhile, the financial atmosphere in Japan will force Tokyo to limit its future defense spending. Although there have been new commitments in certain areas of its military, the overall defense budget of Japan has continued to decline over the past decade and will likely continue to do so.

* The views expressed herein do not necessarily reflect the views of the Asan Institute for Policy Studies.
* The views expressed here are panel overviews of the Asan Plenum. They do not necessarily reflect the views of the author or the institutions they are affiliated with.