Japan’s Emerging Electronic Warfare Capability: A Game Changer in the Electromagnetic Domain?

In March 2020, the Japanese government deployed a cutting-edge vehicle-mounted network electronic warfare system (NEWS) to the Signal School of the Ground Self-Defense Force (GSDF) in Yokosuka, Kanagawa Prefecture. The Ministry of Defense of Japan moreover plans to establish an electronic warfare capability unit of 80 personnel as part of the GSDF at Camp Kengun of Kumamoto Prefecture, located in Kyushu, southwestern part of Japan in April 2021. The unit will collaborate with the amphibious rapid deployment brigade at Camp Ainoura in Sasebo, Nagasaki Prefecture, which has a mission for recapturing remote islands in an event of military emergency. Previously, a cybersecurity unit consisting of some 40 personnel was set up as part of the GSDF at Camp Kengun in March 2019. The electromagnetic spectrum has become a strategically critical domain in the defense of Japan, and the Japanese Self-Defense Forces (SDF) intends to strengthen its electronic warfare (EW) capability in the upcoming years.

Increasing Significance of Electronic Warfare Capability

Electronic warfare, or electromagnetic warfare, is defined as “military action involving the use of electromagnetic and directed energy to control the electromagnetic spectrum or to attack the enemy.” In an electronic warfare, it is important to use the electromagnetic spectrum in terms of three major areas: 1) electronic attack (disrupting, denying, degrading, destroying, or deceiving opponents), 2) electronic protection (preventing a receiver from being jammed or deceived), and 3) electronic support (sensing of the electromagnetic spectrum). For instance, Russian Peresvet as a mobile laser system can emit high-power laser beams to destroy multiple unmanned aircrafts, and Sweden’s Giraffe 8A is capable of automatically selecting frequencies that are invulnerable to jamming. Although electronic warfare includes the term “warfare”, it has been regarded as an appropriate operation for Japan, because “electronic warfare doesn’t involve weapons that kill people” as mentioned by an SDF official.

Historically, Japan’s EW capability dates back to the Russo-Japanese War (1904-1905). In the actual combat, Japan intercepted and analyzed Russian naval radio transmissions, and the ability of signals intelligence is thought to be one of the critical factors to the Japanese victory in the war. In the Cold War period, Japan deployed an EW unit to Camp Higashi-Chitose of Hokkaido in order to intercept signals of the Soviet Union. Even after the end of the Cold War, the EW unit has been considered to be able to intercept signals and collect information from Russia as well as the interior of the Asian continent. Evidently, Japan’s EW capability was developed as a countermeasure against the military threats of Soviet Union/Russia in the past.

Meanwhile, EW capability of Russia has evolved to the extent that astonished and overwhelmed western European countries, especially the North Atlantic Treaty Organization (NATO) member states. During the invasion and annexation of Crimea in 2014, Russia conducted a hybrid war against Ukraine, which combined information warfare, cyberattacks, and EW operations. The hybrid operations by Russia damaged and destroyed command-and-control networks, radar systems, and signals of global positioning system (GPS) of Ukraine. During the 2018 combat in Syria, moreover, the Russian EW system nullified a swarm of drones carrying explosive munitions directing at Russian soldiers, showcasing the significance of EW superiority in modern armed conflicts.

Similarly, it has been observed that China has steadily enhanced its EW capability commensurate with is economic power. Indeed, the People’s Liberation Army has strengthened its EW capability as an important “force multiplier.” Given the increase of its military modernization with a massive military budget, it is no wonder that Chinese EW system could be a game changer in cases of southern remote islands of the Japanese territory. In this sense, Russia’s EW operations in Crimea and Syria have strategic implications for the case of a Sino-Japanese territorial conflict in the East China Sea, although the Japanese government does not admit the existence of such a bilateral dispute.

The Development of Japan’s EW Capability

According to a senior GSDF official, it has been recognized that “Japan is lagging far behind China and Russia in building up [electronic warfare] capability.” In an effort to improve its defense capabilities in the electromagnetic domain, the Ministry of Defense has attempted to acquire EW capabilities, such as, F-35A/B fighters equipped with EW systems and to add EW equipment to the existing F-15 fighters. The Defense Ministry, moreover, has developed a standoff jammer aircraft that can emit disrupting radio waves, non-nuclear electromagnetic pulse (EMP) weapons that could be a game changer by paralyzing opponents’ basic infrastructure system, high-energy laser weapons, and high-power microwave (HPM) weapons which could instantly destroy or nullify electronic components of adversary’s weapons systems. Furthermore, it has been reported that Japan has considered acquisition of the Boeing EA-18 Growler which could enhance Japan’s capability of electronic attack and protection.

With a view to deterring a possible invasion of remote islands, the Japanese government has planned to deploy surface-to-ship missile units to the Nansei Islands. In Amami-Oshima Island of Kagoshima Prefecture, a surface-to-ship missile unit was already deployed, and it is scheduled that a similar unit would be deployed to Ishigaki Island of Okinawa Prefecture, to which the Senkaku/Diaoyu Islands belong in accordance with the recognition by the Japanese government. In essence, therefore, the establishment of Japan’s new EW unit is to improve the defense of Japan facing security challenges and threats in the East China Sea where Chinese vessels enter into the waters surrounding the Senkaku/Diaoyu Islands. Clearly, Japan’s EW capability has been evolving in response to the rise of Chinese military power and a possible military emergency in the remote islands.

A Possible Game Changer in the Electromagnetic Domain

The electromagnetic spectrum became one of the most critical domains in the defense of Japan. Japan’s EW capability has been developed as countermeasures against the military threats of Russia and China. EW operations are regarded as integral part of Japan’s “multi-domain defense force” and its “cross-domain operations” that would include conventional fields (land, sea, air) in combination with new domains (space, cyberspace, electromagnetic). Japan’s defense budget for the fiscal year of 2020 has therefore prioritized the development and acquisition of EW systems, including stand-off EW aircraft and NEWS.

Since Japan has adopted the so-called “exclusively defense-oriented policy” while depending upon the strike capability and extended deterrence of the United States, the development of Japan’s electronic warfare capability has profound strategic implications for the defense of Japan as well as the Japan-U.S. military alliance in the Indo-Pacific. Now that Japan has developed and deployed the EW systems, it is imperative to enhance its training/exercise and education in the electromagnetic domain. Although EW capability is regarded as a nonlethal defense system in Japan, it has an unmeasurable potential to become a game changer technology for its multi-domain defense force.