Is Japan’s sudden decision to halt planned deployments of Aegis Ashore — an advanced, U.S.-made missile defense system — a setback or calculated retreat?
As challenges continue to roil the project and cost-sharing negotiations with Washington loom, observers say the move, attributed by Defense Minister Taro Kono to technical and cost issues, could also be part of a gamble by Tokyo as it recalibrates its defense posture amid a changed security environment.
On Monday evening, Kono cited difficulties in ensuring rocket boosters from the interceptor missiles would fall in areas that did not put lives or property at risk, given current software and hardware issues.
Resolving those issues, he said, would take a significant amount of time and money.
“Considering the cost and time it would require, I had no choice but to judge that pursuing the plan is not logical,” Kono said, adding that he had conveyed the decision to Prime Minister Shinzo Abe on Friday.
Speaking at a news conference Tuesday, Kono revealed more of the details behind the decision.
“Through discussions between Japan and the U.S., the fact was that we made a judgment that improving the software would enable (the rocket boosters to fall in areas deemed safe),” he said. “In retrospect, we can’t refute criticism that our understanding was overly optimistic.”
James Schoff, a former senior Pentagon East Asia specialist now with the Carnegie Endowment for International Peace, said the move will give Japan leverage against the U.S. and buy some time as it considers its options.
“Defense Minister Kono and his team — with Abe’s blessing — want some time to rethink their approach, and perhaps put a little pressure on the U.S. side to help solve some of the technical and cost issues more proactively,” he said.
The National Security Council led by Abe will discuss the matter, and the Defense Ministry will then consider the next move based on those discussions, Chief Cabinet Secretary Yoshihide Suga told a news conference Tuesday. He declined to reveal when the meeting would take place.
At the news conference the same day, Kono said the Maritime Self-Defense Force’s Aegis-equipped destroyers and Patriot Advanced Capability-3 (PAC-3) missile interceptors would continue to play the leading role in the country’s missile defense.
Under Japan’s current two-tiered system, the Aegis destroyers are used to shoot down missiles in outer space, while ground-based PAC-3 batteries can be used to intercept missiles at altitudes of over 10 kilometers in case the Aegis system fails to destroy them.
Suga also revealed that after assessing data provided by the U.S., the Japanese government discovered in late May that a drastic system overhaul would be needed to ensure the rocket boosters would fall inside an area deemed safe.
Despite the tone of Monday’s announcement, it was unclear whether the decision would spell the project’s ultimate doom or if the suspension was merely part of broader considerations.
At least one former defense chief voiced anger over the developments.
“I had been briefed repeatedly that the rocket boosters could be controlled (regarding where they fall), but with this abrupt change, I must wonder whether the Defense Ministry had been lying,” former Defense Minister Itsunori Onodera told a Liberal Democratic Party meeting Tuesday morning.
The government decided in 2017 to deploy the two Aegis Ashore batteries, as part of a bid to bolster the nation’s missile defense shield and ease the burden on its Aegis-equipped warships. The decision had been spurred, at least ostensibly, by the growing threat from nuclear-armed North Korea, which has ramped up the pace of its missile testing in recent years.
But some experts have said that the recent suspension — or even a permanent scrapping of the deployment — would not seriously harm Japan’s ability to defend itself from North Korean missiles.
“I don’t think that this will significantly impact Japan’s defense capabilities,” said Sebastian Maslow, a regional security expert and senior lecturer at Sendai Shirayuri Women’s University.
Japan currently operates a robust lineup of seven Aegis-equipped destroyers and a handful of land-based Patriot missile batteries.
The Aegis Ashore systems, which would be operated by the Ground Self-Defense Force, had been touted as another layer to defend against threats, reducing the workload on the stretched MSDF’s Aegis destroyers and their crews. During the height of the North Korean nuclear crisis, in 2017, those destroyers saw long deployments to the Sea of Japan.
But Maslow argued that ditching the planned deployment would free up money that he said could be spent on pursuing more effective defense capabilities, including Aegis destroyers and submarines that could also be used in other places such as the East China Sea, where the Chinese military has taken on an increasingly assertive posture.
Much, however, will depend on North Korea. While Pyongyang has conducted a number of shorter-range missile tests, it has not routinely fired off longer-range weapons capable of striking Japan since 2017, when it lobbed two missiles over the northern island of Hokkaido.
Abe had also used the purchase of the systems, as well as other weapons deals with Washington, to mollify U.S. President Donald Trump. Trump has long been known to look skeptically on the United States’ military alliances, especially its Asian partners in Japan and South Korea.
“In my view, this is not a setback for Abe, but a well-calculated retreat from the unpopular 2017 decision to purchase more advanced U.S. weapons systems,” said Maslow.
With Trump now preoccupied by the coronavirus pandemic, widespread police brutality protests and his own faltering re-election bid, Maslow said Abe may have judged the timing as ripe for halting the project without facing too much of a backlash from Washington.
“The bottom line in this significant development is that, apart from the reference to cost and technical concerns, Japan’s pullout indicates a clear shift in what the Abe administration is willing to endure as investment in its alliance with a U.S. led by President Trump,” he said.
The Abe administration could also be looking to use the decision as a bargaining chip in upcoming negotiations over sharing the costs of maintaining U.S. troops in Japan. These so-called host-nation support talks are set to begin soon, with the current agreement due to expire next March. Trump and other U.S. officials have repeatedly said that Japan must contribute more to the alliance.
Schoff, of the Carnegie Endowment for International Peace, said the Aegis Ashore issue would be “front and center” in the talks, where it would act as a “mood enhancer” if they are able to make some progress, or as a “mood spoiler” if the talks hit a rough patch.
Asked for comment on the decision, both the U.S. State Department and the Pentagon directed inquiries to the Japanese government.
Tokyo has faced strong local opposition to the deployment, including radiation concerns related to the system’s powerful radar as well as fears the sites could invite attacks by North Korea.
The Defense Ministry was also left red-faced when it was forced to admit it had botched geological surveys of the sites, in Akita and Yamaguchi prefectures, further contributing to the erosion of public trust in the project.
The systems, including their 30-year operational and maintenance costs, have an estimated price tag of ¥450 billion, of which Kono said Japan had already spent about ¥180 billion. The systems were expected to be operational by fiscal 2025 at the earliest.
Schoff said that while the earlier challenges and missteps give Japan “less room for any forgiveness or flexibility in how they handle things now,” the government would continue to quietly work on the issue.
“Japan still wants Aegis Ashore to be part of its missile defense system over the long term, but they needed to take a time out from all these hurdles they kept encountering,” Schoff said.