Following Speaker of the House Nancy Pelosi’s visit to Taiwan at the beginning of August, China conducted four days of large-scale military exercises surrounding Taiwan. These exercises have had clear geopolitical repercussions for Japan. This stems not just from the firing of ballistic missiles into Japanese water during the exercises - which landed just 70 miles away from Japanese territory - but also arises from the vital relevance that both China and Taiwan play in Japan’s economic interests. 

After the drills, Japan signed a statement from the G7 foreign ministers emphasizing their concerns about China’s threatening actions and the G7’s commitment to ensuring peace and stability “in the Taiwan strait and beyond”. This statement prompted China to cancel a scheduled meeting with Japan’s foreign ministers in Cambodia. Hua Chunying, a Chinese spokesperson at the Ministry of foreign affairs declared that China was “strongly displeased” with the G7 statement. Amid the increased tensions, China and Japan eventually held a meeting in Northern China between the Chinese foreign affairs advisor Yang Jiechi and the head of Japan’s national security secretariat Akiba Takeo. 

Both Japan-Taiwan relations and Japan’s position on a potential Chinese invasion of Taiwan have changed over time. Since 1972, Japan has recognized Beijing as the legal government of China but has not recognized China’s sovereignty over Taiwan. Japan’s position on Taiwan’s status has been ambiguous, while they have also been less inclined to criticize Beijing’s attempts to coerce Taipei, highlighting its hopes for a peaceful resolution of the issue between China and Taiwan. Japan’s official Taiwan policy has been therefore one of “working relations on a nongovernmental basis”. Despite this long period of ambiguity, things began to change with Shinzo Abe’s premiership. Before Abe, Japanese officials were very uncomfortable discussing how Japan would respond to a potential Chinese use of force against Taiwan. Abe recognized the serious threat that China posed for Taiwan, and underlined the shared values between Japan and Taiwan, defining Taiwan as an important partner and a precious friend. Even after his resignation as Prime Minister in 2020, Abe continued to emphasize the idea that Japan’s security was closely connected to Taiwan’s security. In line with this, Japanese politicians and strategists have become more explicit about Taiwan’s importance in Japanese security and the need to defend it.

A potential Chinese invasion of Taiwan, therefore, risks putting Japan’s economic and security interests in jeopardy. Taiwan is Japan’s fourth largest trading partner, with their bilateral trade in goods being worth 70bn USD per year. More importantly, Taiwan is the greatest source of high-end semiconductors which are indispensable for Japan’s manufacturing industry. This is a crucial issue for Tokyo’s economy, as Taiwanese microchips are used by Japan to manufacture cars, video games, and electronics. Japan would be forced to react to an invasion that would cause considerable problems for its economy. This is because If China was in possession of Taiwan, particularly its military installations across the South China Sea, it would in turn have major influence over regional shipping, and could mean ships directed to Japan take more inefficient routes. With more than 40% of Japan’s maritime trade passing through the South China sea, this would cause major reverberations throughout the Japanese economy. 

Furthermore, Japan’s national and economic security would be threatened if Taiwan were attacked, as there are chances that Japan could also be pulled into the military conflict. Indeed, Japan hosts the US’ armed forces at several significant military bases. In line with Abe’s thinking that a Taiwan contingency is also a contingency for Japan, China could attack the US military forces in Japan if the US tries to defend Taiwan. Many analysts have suggested it is highly unlikely that Japan would rush to aid Taiwan, and would more likely support the island nation as western nations have done in the Ukraine conflict. Japan’s non-governmental relationship with Taiwan also makes it difficult to arrange a military response. 

Moreover, article 9 of the Japanese constitution clearly states that Japan renounces war, and in fact the use or threat of force more generally, to settle international disputes. Nonetheless, under article 9, Japan is allowed to use force if it is attacked. Additionally, some recent interpretations of article 9 maintain that it may be legitimate for Japan to use force in case of an armed attack against a foreign country with close ties with Japan, and could therefore constitute a threat to Japan’s survival. Due to the disastrous economic consequences that an invasion could have and the prospect of a Chinese attack on US military forces in Japan, it is very reasonable to see such an invasion as a threat to Japan's survival. Considering also the recent more militaristic inclinations of the Japanese establishment since Abe, the chances that Japan could defend Taiwan from a Chinese attack are increasing.