Japan is well positioned to deter and counter violations of its territorial airspace, officials and analysts said following recent incursions by Russian and Chinese military aircraft.
“Japan will continue to develop the capabilities to deploy aircraft and other resources to monitor and push out [Russian aircraft] from Japanese territory,” Stephen Nagy, an international relations professor at Japan’s International Christian University and a senior fellow at the East Asia Security Centre, told FORUM.
Stronger monitoring and response capabilities, including advanced radar and aircraft, along with Japan’s long-standing alliance with the United States, can deter potential adversaries such as the People’s Republic of China (PRC) and Russia, Nagy and others contend.
In September 2024, a Russian military surveillance plane crossed into Japanese airspace three times near Hokkaido, Japan’s northernmost prefecture, prompting Tokyo to scramble F-15 and F-35 fighter jets, according to Japan’s Defense Ministry. That incursion followed an incident a month earlier in which a PRC surveillance aircraft violated Japanese airspace near the southwestern prefecture of Nagasaki, an episode Beijing claimed was “completely accidental,” according to Japan’s Kyodo news agency.
After Russia’s incursions, Japanese Defense Minister Minoru Kihara said that Japan remains vigilant regarding any such moves by the PRC and Russia, including into the nation’s maritime territory. He vowed Japan would “take all possible measures” to detect and counter such violations.
Nagy said Japan “strives to maintain a comprehensive understanding of Russia’s assets within the region and its coordinating of activities with the Chinese, and attempts to get as much information as possible in terms of Russia’s intentions in the northern [Japanese] territories, and broadly within the region.”
Defending Hokkaido is a priority for Tokyo, he said, given the island’s proximity to North Korea and Russia and the importance of the surrounding maritime territory to shipping.
“We are seeing a widespread investment in the region [by Japan] in terms of monitoring technology for space, air and maritime, and this is important for building a strong, comprehensive domain awareness to be able to best respond to Russia,” Nagy said.
According to Japan’s 2024 Defense White Paper, Russia has been expanding its military presence on the Kuril Islands near Hokkaido, an archipelago that Russia controls but Japan claims. This includes upgraded facilities for ground forces, deploying new fighter aircraft, coastal anti-ship missile systems and other weapons, and conducting large-scale military exercises.
In response to Russia’s buildup, Japan has strengthened its air and maritime defenses with continuous surveillance. The Japan Air Self-Defense Force operates 28 radar sites and early warning aircraft to monitor the nation’s airspace. The Japan Maritime Self-Defense Force (JMSDF) conducts surveillance with P-3C aircraft, escort vessels and other assets, and key territorial waters are guarded by the JMSDF and Japan Ground Self-Defense Force observation posts.
Meanwhile, the U.S. maintains a robust presence in Japan and the broader Indo-Pacific, including regular joint exercises to enhance regional security and deter potential aggressors, Nagy said. Those efforts are bolstered by Tokyo’s enhanced monitoring assets in northern Japan and intelligence-sharing agreements.
“Having strong and comprehensive maritime domain awareness capabilities and space and air capabilities located in Hokkaido helps the United States understand how Russia is functioning within the region,” he said.
