Japan’s unexpected cancellation of its major Aegis Ashore missile defense project will hinder its response to the increasing North Korean missile threat, as well as raise significant doubts about Tokyo’s ability to implement necessary security agreements with the United States. After warning of a deteriorating security environment, Tokyo has now abandoned a viable means of addressing a threat to the Japanese homeland and U.S. forces stationed there.

Tokyo will now engage in yet another security review to ponder alternatives while the North Korean missile threat continues to grow. Prime Minister Shinzo Abe advocates Japan acquiring offensive strike capabilities as one option. But, due to Japan’s largely pacifist populace, such a step would be far more controversial and difficult to achieve than the defensive Aegis Ashore initiative.

Aegis Ashore Adrift

In June, Defense Minister Taro Kono explained that Japan would suspend construction of two Aegis Ashore ballistic missile defense sites due to the potential for the interceptor missile’s first-stage booster to fall onto populated areas. To prevent that danger, the missile would have required a 10-year, $1.8 billion refurbishment.REF Needless to say, the risk from a fallen booster is far less than the devastation from a North Korean nuclear warhead hitting Japan.

Other likely factors in the decision include the overall cost of the program, inept handling of the site-selection process, and government unwillingness to press national objectives over local resistance. The Aegis Ashore program was initially estimated to cost $2.15 billion to purchase, operate, and maintain over its 30-year operating period, but the total had eventually increased to $4.1 billion.REF

The Abe Administration has warned that “North Korea in recent years has launched ballistic missiles at unprecedented frequency, rapidly improving its operational capabilities such as simultaneous launch and surprise attack [which are] grave and imminent threats to Japan’s security.”REF

To date, Japan has invested heavily in ballistic missile defense, including seven (soon to be eight) Aegis-equipped guided-missile destroyers outfitted with SM-3 interceptor missiles and the Patriot PAC-3 land-based system. In 2017, Tokyo decided to build two Aegis Ashore sites by 2025 in order to free up the Aegis ships for other missions, such as maritime security. The Aegis Ashore units would have provided missile defense for the entire country, unaffected by weather or staffing shortages that have affected the Aegis ships.

The Ministry of Defense highlighted that the more capable SPY-7 radar of the Aegis Ashore would “drastically enhance Japan’s capabilities to respond to ballistic missiles, and includes enhancement of the capability against lofted trajectory launches and response to simultaneous majority attacks compared with Aegis-equipped destroyers.”REF

No Good Alternatives

Tokyo is now considering other alternatives, such as procuring two additional Aegis ships, purchasing the Terminal High Altitude Area Defense (THAAD) missile defense system, or deploying Aegis Ashore on “megafloats,” large floating structures that can be used as an artificial island base. Each alternative has significant shortcomings. Two Aegis-equipped ships would cost about the same as the two Aegis Ashore sites and Japan already has difficulty manning its existing fleet.

The THAAD system would require six sites rather than the two of Aegis Ashore, could be even more expensive, and would be vulnerable to the prevalent “not in my backyard” local resistance endemic to military construction projects in Japan. THAAD would also not be able to engage incoming missiles at as high an altitude as SM-3 missiles. Megafloats are vulnerable to severe weather and enemy attack.

Since the Japanese National Security Council affirmed Defense Minister Kono’s statement, there has been confusion about whether Tokyo cancelled or suspended the project. Former Defense Minister Gen Nakatani, a member of the government panel assessing alternatives, suggested that the Aegis radars and interceptor missiles could be deployed at separate sites, removing the danger of falling booster stages to the population.REF

Developing Strike Capabilities Is Problematic

Prime Minister Abe announced that an alternative to Aegis Ashore being considered was Japan developing offensive strike capabilities against enemy missile targets. Abe reportedly commented privately, “With the advent of new [North Korean] missiles, there’s a limit to what can be done with a shield. We have to have a halberd.”REF

Though such capabilities have been periodically broached, such an option would be highly contentious within Abe’s political coalition, the Japanese populace, and Japan’s neighbors. As early as 1956, Japanese officials declared that attacking enemy bases could be justified in terms of the right of self-defense. Since then, policymakers have emphasized that attacking a North Korean missile that was preparing to attack Japan would be consistent with the country’s “peace constitution.”

While some policymakers advocate acquiring cruise or ballistic missiles to conduct attacks prior to Japan absorbing a missile strike, Japanese officials typically emphasize that the more prevalent interpretation has been that Tokyo would attack only after an initial attack on Japan, and that missiles would be implemented only to prevent additional attacks.REF

It is unclear which offensive capabilities Abe might be considering. In its most recent defense documents, Japan indicated it would purchase medium-range, air-launched, standoff missile attack capabilities, including the Joint Strike Missile with a 350-mile range, the Joint Air-to-Surface Standoff Missile-Extended Range with a range of 540 miles, and the Long Range Anti-Ship Missile, as well as developing hypersonic guided missiles.REF

Negative Ramifications

Japan has killed a defensive bird in the hand for potential birds, including a highly contentious strike bird, in the bush. Having been warned of the North Korean missile threat, the Abe administration will now have to rely on defense capabilities it previously deemed insufficient.

Japan’s decisions may also have consequences for its alliance with the United States. Washington saw Aegis Ashore as providing enhanced defense for the 50,000 U.S. military personnel in Japan as well as freeing up U.S. Aegis-equipped destroyers for other duties in the western Pacific.REF

What Washington Should Do

In order to augment allied defenses against the growing North Korean missile threat, Washington should:

• Urge Japan to move forward on missile defense. Since Tokyo’s 2017 decision to build two Aegis Ashore sites, North Korea has continually developed, refined, and produced its missile arsenal to target Japan with nuclear weapons. The North Korean regime has conducted missile-firing exercises practicing its war plan to strike U.S. bases in Japan. Pyongyang has also identified Kyoto, Nagoya, Osaka, Tokyo, and Yokohama as targets.REF The Abe administration should ensure that it has the most robust missile defense system possible.
• Coordinate ballistic missile decisions with Tokyo. Tokyo’s unexpected reversal of the 2017 decision does not seem to have been well coordinated with the U.S. The bilateral and integrated missile defense system affects both nations and, as such, should entail carefully synchronized strategies. Tokyo made a major decision without an alternative game plan. That should not occur again.
• Urge Japan to assume additional security responsibilities, but to move carefully on strike capabilities. The U.S. should welcome any expansion in the Japanese security role to augment alliance capabilities. But, rather than a substitute for missile defense systems, Japanese strike capability is still only at the theoretical debate stage as to whether such a role should even exist. Tokyo has yet to articulate strike policy, strategy, doctrine of employment, triggering events, procurement, deployment, or how offensive systems would train in Japan. Such decisions should be made in an alliance framework, in part, to allay South Korean concerns that would inevitably arise.

Conclusion

Progress in altering Japan’s security posture has always lagged behind faster-moving regional threats. Any change in Japan’s security posture requires an inordinate amount of time, effort, and outside pressure to overcome political and public resistance—like pulling a cart with square wheels.

Japan’s abrupt cancellation of the two Aegis Ashore sites is uncharacteristic, yet at the same time consistent with a broader trend of unwillingness to push against local resistance, even at the cost of degrading Japanese or allied deterrence and defense capabilities. Gaining local support for military projects is important given the landscape of Japanese law and politics, but must be weighed against the greater security good. Common threats are best addressed by common, well-coordinated strategies. Surprises are not good for alliance planning.

Bruce Klingner is Research Fellow in Northeast Asia in the Asian Studies Center, of the Kathryn and Shelby Cullom Davis Institute for National Security and Foreign Policy, at The Heritage Foundation.