The threat of ballistic missile attacks from North Korea and the increasing Chinese incursions into the Diaoyu / Senkaku Islands has reignited debate on Japan’s defense options, including the development of overseas “strike capabilities.” While this debate has stimulated the normal political sensitivities, less attention has been given to the tactical, strategic, and budgetary considerations that also shape Japan’s defense choices. While this would be a major symbolic shift given Japan’s post-war commitment to the principle of senshu bōei, or exclusively defensive defense, the question remains of whether the ability to conduct precision strikes inside foreign territories would constitute a major strategic enhancement of Japan’s military power. In fact, it may not be the game changer that hawkish proponents hope for or that pacifist skeptics fear.
Since 1956 the Japanese government has insisted that striking missile positions in foreign countries once an attack has begun is a constitutionally admissible form of self-defense. In a now famous 1956 Diet statement, Prime Minister Hatoyama Ichirō bluntly stated “I cannot believe that it is the constitution’s intention for us to sit and wait for our own destruction”. Hatoyama argued that the constitution did not prevent Japan responding to overseas missile attacks by targeting foreign missile bases if no other options existed, as long as the response was limited to the “the minimum measures unavoidably necessary.” While there is technical debate about whether this allows preemption, Japan’s eschewal of long-range, foreign territory strike mission and ultimately reflects non-constitutional considerations of plausibility, strategy, and political and diplomatic sensitivity.
Geopolitical developments and changes in modern warfare soon sparked a reassessment of Japan’s options for dealing with regional threats. In early 2003, less than a month after North Korea demonstrated that it possessed a working missile with the speed, range, and accuracy to reach Japan within ten minutes, the United States and its allies initiated its second war against Iraq. Like the 1991 Gulf War, the Tomahawk Land-Attack Cruise Missile took center stage as U.S. and British militaries relentlessly and precisely dismembered Iraq’s political and military infrastructure. Tokyo remained attentive, and while Japan did not participate in the fighting, many wondered if the Tomahawk missile was the weapon that would allow Japan to defend itself from overseas missile attacks when “unavoidably necessary”.
Many wondered if the Tomahawk missile was the weapon that would allow Japan to defend itself from overseas missile attacks
The Japan Defense Agency (JDA) head in 2003—and perennial candidate for prime minister of Japan—Ishiba Shigeru, certainly thought so. He explicitly affirmed that the Tomahawk was not considered a constitutionally proscribed “exclusively offensive” weapon system that could be adopted solely for causing catastrophic destruction inside another country’s territory. In response to questioning by Maehara Seiji in the March 27 National Security Committee of the Diet, Ishiba set off a media frenzy by commenting that the JDA had already started investigating the acquisition of the U.S.-developed Tomahawk. As the archetypal symbol of both national muscle and technological precision, one Japanese defense official at the time marveled at how the Tomahawk “could hit a soccer goal post in Hakata if launched from Tokyo.” Prime Minister Koizumi Junichiro backed up his cabinet colleague, saying “isn’t it fine to explore the possibility? We’re committed to senshu bōei; this won’t change.”
This discussion was placed on the back-burner until the second Abe administration, owing in part to Japan’s pursuit of interceptor-based ballistic missile defense. Most recently, a Liberal Democratic Party (LDP) study group stacked with former defense ministers was launched to reevaluate “missile defense” options after the suspension of the Aegis Ashore system. In this committee, former Minister of Defense Nakatani Gen and former Deputy Foreign Affairs Minister Sato Masahisa went on record in strong support of Japan officially embracing the development of a Tomahawk-enabled long-range strike capability. Nakatani expressed a sentiment common among some commentators in recognizing foreign territory strike as an official Japan Self-Defense Forces (JSDF) mission: “we cannot take for granted that the United States will retaliate if we are attacked. There is a need for us to enhance deterrence by developing our own retaliatory capability.” Using similar logic, it was notable that the centrist Nikkei notably supported the need for counterstrike capabilities.
Also notable, however, is that former proponent Ishiba has argued against jumping from a cancelled Aegis Ashore to enabling long-range strike, calling it a leap in logic. Given the military balance in East Asia vastly differs from 2003, Ishiba and other commentators are engaged in a debate over whether Japan committing to strike missions in foreign territories will really enhance deterrence against North Korean missile attacks. Whether fielded as an autonomous capability or developed and deployed in cooperation with the United States, Japan will need to purchase and familiarize itself with large numbers of high-end, high maintenance, and expensive support systems to have even partial success in any “missile defense” strike mission inside North Korea. Few serious analysts believe preemption has a high chance of success, and the most convincing scenario for foreign territory strike is likely damage mitigation and suppression of follow up attacks. Even a robust foreign country strike capability fielded in cooperation with the United States will not be the silver bullet some proponents envision.
Acquiring a full range of equipment raises even more important questions about the purposes of Japan’s military posture and how it is supported by Japan’s still-limited military budget. Foreign territory strike will, after all, be one more capability set to compete for the Japanese defense yen. Under Abe, the defense budget has been given sanctuary (聖域) status and protected from cuts. The “record” increases in Japan’s budget have nevertheless been less impressive than sensationalist media headlines indicate (see table 1), especially in comparison with Japan’s neighbors (see table 2). With modest 1 percent year-on-year increases and no major step change in spending on the horizon, Japan is unlikely to move beyond the symbolic 1 percent of GDP mark any time soon.
Furthermore, rising maintenance costs soak up a significant amount of new spending and after 2017 maintenance costs shot up due to a higher intensity of JSDF operations both close to home and abroad since 2017 (table 3). Currently, only one-sixth of each new defense yen goes towards procuring equipment. However, with more high-end systems being purchased from overseas and prioritized for payment, resource scarcity is contributing to procurement and system rollout delays, a situation COVID-19 will likely make worse. There is also the long-term worry that even with constant incremental increases in defense spending, some of the equipment’s “core” capabilities will be eroded or stagnate as the JSDF adorns itself with scattered pockets of high-end capabilities and maintenance cost increases.
Stretching Japan’s budgetary and recruitment situations too thin will only make it harder to address its maritime challenges
The maritime domain is where many of Japan’s areas of operational excellence and greatest value-add to the alliance lay and will do so for some time to come. However, there has been a significant crowding out of shipbuilding in favor of the purchase of high-end U.S. aircraft (table 4, table 5), only slightly offset by increased Japan Coast Guard shipbuilding. Recruitment is arguably even more of an issue than hardware for the MSDF. Adding another mission and the required support systems (many aerial) will only exacerbate the budgetary and recruitment situations. This will only make it harder for Tokyo to address the profound maritime challenges it faces to its southwest.
Addressing those pressures through better funding and equipping of the JSDF and the JCG will most certainly not hurt the alliance. But, as RAND’s Jeffrey Hornung notes, the cancellation of Aegis Ashore along with prompt debate over Japan’s strike capabilities was not necessarily seen fondly by the U.S. security establishment. Not only was Aegis Ashore good for the alliance for the functional operation of regional missile defense and for U.S. territorial defense, it would have freed up U.S. and Japanese destroyers to concentrate more on China southwest maritime challenge. If ship-launched Tomahawks become the main foreign territory strike option, then Japan’s Aegis-equipped destroyers may instead become the key platforms for the LDP’s proposed “missile interdiction” in foreign territory as well as for midcourse missile interception.
The cancellation of Aegis Ashore was not necessarily seen fondly by the U.S. security establishment
Given the pressures on Japan’s defense budget, and the upcoming negotiations over increasing host nation support, Japan will want to emphasize its alliance contribution going forward in the most convincing way possible. The United States may indulge Japan’s desire for strike capabilities but will otherwise be unimpressed with the current set of proposals. There are also highly important (but perhaps symbolically boring) enhancements Tokyo could make to Japan’s military posture and SDF methods of operating—such as base hardening and dispersal and better interoperability between the three SDF services—that would be very valuable to Japan’s own defense as well as alliance functioning. There is also the issue of insufficient R&D investment to future-proof Japan’s military capabilities (table 5).
Being arguably even more hawkish than Abe, Ishiba’s contemporary skepticism over foreign territory strike is thus more about the need to think carefully about the full, long-term cost of capability acquisition, likely mission effectiveness relative to expressed goals, how this mission adds to the functioning of the U.S.-Japan alliance, and the messages communicated regionally in terms of faith in the alliance and nuclear umbrella.
One cannot deny the foreign territory strike debate, and the acquisition of the Tomahawk in particular, have their own totemic symbolism for many revisionist conservative politicians who want to go beyond the “post-war regime,” especially in absence of constitutional change. Arguably, therefore, both the Japanese left and right need to engage in “calm and scientific thinking” regarding any genuine commitment to the development of this capability.