America and Japan in a Post-INF World


How long do estimates suggest it would take the People’s Liberation Army Rocket Force to destroy all major U.S. air, naval, and logistics bases in Japan? Some have argued that the answer is not days, but hours. Let’s come back to this though, after first setting the record straight on how the U.S.-Japan alliance has found itself in such a dire position.

After five years of attempting to bring Russia back into compliance with the Intermediate-Range Nuclear Forces (INF) treaty, earlier this month the United States, at the urging of Congress, exercised Article 15 of the treaty and notified Russia of its intent to withdraw in six months. Unsurprisingly, Russia subsequently wasted little time in officially suspending its participation in the treaty.

As a result of Russia’s decisions, following Aug. 2, 2019, the U.S. Department of Defense will now be able to test and deploy ground-based cruise and ballistic missiles with a range of 500 to 5500 kilometers. The implications of this decision for Europe and the NATO alliance have been discussed at length. What has not been explored is how a post-INF world, and particularly the conventional missile aspects of said world, will affect the U.S.-Japanese alliance and America’s defense posture in East Asia. No longer restrained by the treaty, the United States will be able to work with Japan to explore a series of relatively affordable, near-term options to bolster the conventional military balance with China and impose new costs on Beijing’s military planners. The alliance will need to move carefully and with purpose to take advantage of these newfound benefits.

As the treaty comes to an end it is important to reflect on the unique role Japan played in its final negotiation during the mid-1980s. At the time, the United States and European countries were ready to accept the Soviet Union’s plan for a regional ban of intermediate-range weapons solely in the European theater. However, Tokyo objected to a geographical limitation and maintained that the treaty should be global in scope because the Soviets could move a residual SS-20 ballistic missile force to the Far East and threaten regional security in Asia. Japanese Prime Minister Yasuhiro Nakasone insisted to President Ronald Reagan that any INF agreement should not be perceived by the Japanese public as disadvantageous to Japan and that Asian concerns should be given the same consideration as European concerns. Japan’s intervention was instrumental in leading to the global elimination of ground-launched, intermediate-range weapons as part of the final 1987 treaty agreement.

Three decades later, INF-range missiles have proliferated to East Asia, including North Korea and China (while South Korea is currently developing them). The proliferation of ground-launched ballistic and cruise missiles has rapidly shifted Tokyo’s security environment and the military situation facing the U.S.-Japanese alliance. Not a party to the treaty, China has invested heavily in a modern military and has specifically prioritized a conventional missile force that can hold naval ships and military bases at risk across East Asia. Beijing owns the largest arsenal of such missiles in the world and is now estimated to have 1,400 to 1,800 of these weapons. The result is a China more confident in its conventional military prowess and the continued erosion of regional strategic stability. The United States relies on a series of naval and air bases in Japan at Kadena, Sasebo, Iwakuni, Yokosuka, Misawa, and Anderson in Guam to generate offensive combat power. By targeting these critical nodes and other naval assets in the theater in a quick, sharp strike, China could move to paralyze American power projection and present the United States and the alliance with a fait accompli. If this trend continues, Beijing could conclude that they can deter U.S. military intervention and may find the option to use force to achieve its objectives in a place like Taiwan, or the Senkakus, more appealing.


With the arrival of a Chinese military that can pose a credible military threat to the U.S.-Japanese alliance, Nakasone’s original dictum that Asian concerns about intermediate-range  weapons should be given the same consideration as European concerns holds truer than ever. The treaty has placed an undue burden on an American joint force that must operate from great range across Asia’s geography and has to rely on a limited number of bases to project power from.

The INF Treaty also forces the United States to exclusively use air-launched and sea-launched cruise missiles fired from expensive platforms that have finite munitions magazine depth. As a result, the United States faces a regional “strike gap” against Chinese land and sea targets. Just as Nakasone did not want Asia to bear the cost of a limited INF Treaty in 1987, Japan and America’s Asian allies should not be expected to carry the consequences of the failed treaty in 2019 and beyond. In many ways East Asia has already been living in a post-INF world, with only the United States continuing to abide by the Cold War-era restrictions.

America’s decision to finally recognize the failure of the treaty means that the U.S.-Japan alliance can now consider a new defense agenda that aims to strengthen the alliance and bolster the military balance in East Asia. Adm. Phil Davidson recently testified to the Senate Armed Services Committee on the utility of ground-based systems, concluding that “for (Indo-Pacific Command) to have a land-based component with (intermediate-range) capability restores maneuver to the force, making the air, maritime and land component much more viable in any warfare scenario and presents a much greater challenge for adversaries to threaten.”


The United States should start by launching a study, including a series of war games, about the most effective mix of ground-launched systems to address the strike gap with China. This will serve to offset the striking power of air- and sea-launched platforms and introduce new dilemmas for the PLA that will complicate their planning and potentially force additional investments in defensive systems. Given the importance of the U.S.-Japanese alliance for regional stability and the unique advantage of Japan’s geographical location, this study should be conducted in consultation with the government of Japan.

The INF Treaty prohibited any kind of ground-based, intermediate-range missile system regardless of the target, meaning even surface-to-ship missiles were prohibited. Considering the geographic characteristics of the Western Pacific, one lucrative choice for the alliance would be the development of a surface-to-ship cruise missile. Japan already has a surface-to-ship missile capability with a range of roughly 200 km, but this limited range makes it insufficient to contribute to coordinated strikes with air- and sea-launched missiles. Given Japan’s experience with surface-to-ship missiles, Washington and Tokyo would benefit most in the near-term from the joint procurement of a surface-to-ship cruise missile with a range of 500 to 1000 km. This would give the alliance the ability to conduct multi-azimuth and time-coordinated strikes against adversary’s surface ships throughout the East China Sea.

This capability could be tested and deployed expeditiously by integrating an existing mobile launcher with a surface-to-ship munition that is currently in production like the Long-Range Anti-Ship Missile or Naval Strike Missile. The U.S. military is already procuring both munitions and Japan decided to procure a version of both in its recent National Defense Program Guidelines. Instead of developing an entirely new munition, this option presents a relatively inexpensive and near-term way to bring this new capability into the alliance arsenal.

While a surface-to-ship missile of this range would need to be deployed to the first island chain to be effective, the United States does not have to base this new surface-to-ship missile battery in Japan. Instead, the capability could be based forward in a location like Guam or Alaska where the United States Air Force has large transportation aircraft. This would allow it to be positioned in the theater and able to move rapidly forward to conduct joint exercises with Japan’s Ground Self-Defense Force or as a flexible deterrent option to signal alliance resolve during a crisis.

Finally, over the medium-term, the alliance should consider the option of developing land-attack cruise missiles with a range of 1000 to 1500 kilometers to offset the current strike gap between China’s ground-based strike power and America’s air- and sea-launched striking power. This could include the Tomahawk or the Joint Air-to-Surface Standoff Missile integrated on a mobile ground launcher. If the United States could deploy conventional ground-launched systems that could hold China’s interior at risk, it would potentially force greater Chinese investment in missile defense systems to protect their military infrastructure. Every dollar spent on a defensive system is a dollar Beijing cannot devote to offensive systems along its coast or in its maritime and aerospace forces. That is the sort of competitive strategy alliance planners should be eager to exploit and that the 2018 National Defense Strategy specifically mandates. There is also the possibility that the development of a land-attack cruise missile might also be leveraged in the future to pressure China to discuss a regional arms control regime, just as the Pershing II deployment shaped the Soviet’s choice to start INF Treaty negotiations in the early 1980s. This is an important and overlooked point by the arms control community today. As early as 1980-81, Reagan offered the Soviets a zero-zero agreement to eliminate all INF missiles. Moscow continually refused Reagan’s offers until America and the NATO alliance demonstrated that it could and would deploy ground-launched Pershing II and Tomahawk missiles.

Critics to our suggested approach will contend that Tokyo will never be able to accept the deployment of cruise missile batteries to Japan following the withdrawal of the INF Treaty. First, despite the focus on nuclear weapons in the original treaty, it must be clear that we are only discussing the utility of conventional intermediate-range weapons. Second, critics of the U.S. decision have insisted Japan is opposed to INF withdrawal, pointing to press reports where Chief Cabinet Secretary Yoshihida Suga said INF withdrawal was “undesirable.” But Suga carefully placed the blame on Russia in his full statement, saying that “the situation under which the Treaty is forced to be terminated is undesirable (author emphasis).” Third, the types of munitions we are proposing already exist in the U.S. arsenal and many of them are stored at American bases in Japan for loading on sea and air platforms today. In Japan, the Marines already employ the ground-launched missile systems that would be required for these munitions. Fourth, just like nuclear aircraft carriers, the V-22 Osprey, and missile defense systems in the past decade, we agree that any new capability introduced into Japan will require careful alliance consultation and coordination. Fifth, the fact that the decision to accept the deployment of ground-based strike systems would have great political significance magnifies the effect of its deployment as a flexible deterrent option. Finally, to mitigate a “fear of entrapment” in Japan, both Tokyo and Washington must deepen intelligence sharing and consultation on allied defense strategy to form a common perception of the strategic situation and a shared sense of required capabilities. Fortunately, this process has already begun, including on the subject of anti-ship missile capabilities, as demonstrated during the most recent Rim of the Pacific military exercise. The key point is that, just as has been the case in the past, it is the responsibility of alliance managers to work through issues that can be sensitive politically. It is also their duty to have a frank discussion about the challenges the alliance faces and the capabilities required to maintain a favorable conventional military balance.

A decision on whether to accept the deployment of ground-based strike systems will hold some controversy in Japan. However, how to offset the strike gap is one of the most important national security questions Tokyo faces. Therefore, this should not be treated as traditional “gaiatsu,” or listening to “what the American thinks” first and then discussing “how the Japanese responds to the American request.” Since the strike gap is a serious physical challenge to the Japanese homeland rather than the American homeland, what Japan should do first is to discuss how the alliance should address the strike gap, and then cooperate with or ask support from Washington to offset this gap. Based on serious assessments of strategic reality, the answer to this controversial issue must be found by the Japanese government and public.



Eric Sayers is an Adjunct Senior Fellow at the Center for a New American Security (CNAS). He previously worked as a Professional Staff Member on the Senate Armed Services Committee and as a Special Assistant to the Commander at U.S. Indo-Pacific Command. He is a member of the Asia Strategy Initiative, a multi-year project to generate new ideas for the U.S.-Japan alliance sponsored by the Sasakawa Peace Foundation.


Sugio Takahashi is a Chief of the Policy Simulation Office, National Institute for Defense Studies (NIDS) in Tokyo, Japan. He previously worked in the Office of Strategic Planning at the Japan Ministry of Defense as a Deputy Director where he was on the drafting team of the National Defense Program Guidelines of 2010 and 2013. He is a member of the Asia Strategy Initiative, a multi-year project to generate new ideas for the U.S.-Japan alliance sponsored by the Sasakawa Peace Foundation.

Image: U.S. Air Force photo by Senior Airman Marcus Morris