[KiHo Han Column] China’s ‘Ban on Japan’ — Why It’s No Laughing MatteR

Dr. Kiho Han, Director (Associate Professor) of the Research Laboratory at the Ajou University Institute for Unification Studies and Affiliated Research Fellow at CUKPE

Chinese authorities and Chinese people are sending a sharp message to both South Korea and Japan through selective choices in the tourism sector. While Sino-Japanese diplomatic relations worsen, South Korea ranked first last week in terms of outbound air bookings by Chinese travelers. Given that in 2024 Korea came in third in China’s outbound travel (after Japan and Thailand), and considering that in the same year Chinese tourists most often picked Japan (and vice versa), this diplomatic conflict between China and Japan may give South Korea a reflexive advantage—at least for a while.

For us, who have overcome geopolitical constraints through trade exports, the China–Japan conflict could become another diplomatic crucible. Recently, at the Seoul Foreign Affairs Forum on the 18th, the Chinese ambassador to Korea, Dai Bing, and the Japanese ambassador to Korea, Koichi Mizushima, both referred to Korea as an “inseparable partner” and underlined a “strong Korea–Japan relationship.”

Holding popcorn in hand, the reflexive benefits we’re enjoying from the China–Japan dispute are fleeting. “Enjoyment” soon becomes “entrapment.” The movie will end, and procedurally and afterward, we will have to face the harsh reality brought by this geopolitical conflict. This marks the full-fledged return of Northeast Asian geopolitics, which we had somewhat forgotten amid U.S.–China strategic competition.

Long before Japan’s current situation, the ban on Korean culture (the hallyu ban) began in earnest in 2017, triggered by China’s opposition to the deployment of the THAAD missile-defense system in 2016. That ban remains very much in effect. This current conflict will not just be a fleeting incident.

The roots of the China–Japan conflict lie in their different perceptions over a possible crisis in Taiwan. Historically, Taiwan became a Japanese colony through the First Sino-Japanese War (1894–1895) and the Treaty of Shimonoseki, and was returned to China after World War II. The special status of Taiwan—separated from the mainland after the Chinese Civil War—is the fundamental cause of their competing claims over territory and historical memory. The “Taiwan issue” is a geopolitical core of China–Japan relations: China’s core interest is the “One China” principle, while Japan’s security interest is tied to Taiwan’s strategic role.

Taiwan serves as a “non-sinking aircraft carrier” that constrains China’s maritime expansion and is vital for Western Pacific security. From Japan’s perspective, Taiwan lies on a crucial front for energy routes and security — if China controls Taiwan, it poses a direct threat to Japan’s security and economy.

Against this background, on the 7th of this month, Japanese Prime Minister Takaichi made a statement saying “a Taiwan contingency means a Japanese contingency.” The next day, Xue Jian (薛劍), the Chinese Consul-General in Osaka, responded with inflammatory language, threatening to “cut off a neck that sticks out without hesitation.” By using such rhetoric, he rejected the idea of a “deep trust” friendship (the Chinese four-character idiom wengjing zhijiao, or “neck-cutting friendship,” which actually symbolizes deep trust) and instead sent a message that fanned the flames. As expected, the Chinese government defended Xue, fueling controversy over “wolf-war diplomacy”—including high-level Chinese officials distributing satirical cartoons of Takaichi.

China’s response to its core interests was swift. Among the measures: urging restraint on travel to Japan, restricting study abroad, banning seafood imports from Japan, and refusing to participate in the January trilateral Korea–China–Japan summit. The possibility of a full-scale trade war was even raised, with China using rare earth export restrictions as a card. Though limiting rare earth exports would also hurt China, such a move could inflict tremendous damage on Japan, especially in its high-tech and manufacturing sectors—this would be a replay of the 2010 Senkaku Islands dispute. Yet Prime Minister Takaichi, buoyed by support around 70%, has indicated she will not retract her “Taiwan remarks.” For the Korean Peninsula, this trajectory of events is clearly bad news.

First, maintaining strategic ambiguity in Korea’s diplomacy is becoming much more difficult. In the short term, Korea’s value may rise on both sides (China and Japan), but by adding Japan as another variable to the existing U.S.–China dynamic, we risk losing out both in security (cooperation with the U.S. and handling North Korea) and in economics (Korea–China–Japan cooperation). Realistically, we need China’s cooperation on North Korea’s nuclear issue, and at the same time, to minimize China’s sensitivity about our nuclear-powered submarine plans while drawing in Japan’s support. Moreover, the U.S. has long demanded “strategic flexibility” from U.S. forces in Korea, implying that they could be deployed beyond the peninsula — including in a Taiwan contingency. With U.S. officials increasingly calling on allies to raise defense spending and expand their roles amid the China threat, the China–Japan conflict risks becoming a microcosm of the broader choice Korea faces in U.S.–China competition. Washington may demand that Korea show clarity (as Japan has) on Taiwan, testing our “loyalty” to the U.S. The nuclear-submarine project in U.S.–Korea cooperation is expected to take at least 10 years, with many uncertainties about its purpose. Still, strengthening our own defense capacity remains crucial. But geopolitical variables like China–Japan conflict — which we cannot control and which could spark an arms race — should be minimized.

Second, there is the risk from a prolonged China-led “Korea–Japan ban” and intensifying conflict. If the Sino-Japanese dispute drags on, the resulting geopolitical risk in East Asia could weaken the yen, strengthen the dollar, and upset our domestic stock market. Economically, we must consider the hit to exports and supply chains. China dominates key mineral supply chains — rare earths, graphite, and other critical minerals needed for semiconductors, electric vehicles, and batteries. If China weaponizes these resources, not only Japan but also Korean companies embedded in those supply chains could suffer severe disruption. Additionally, if the U.S. weighs Korean loyalty via Japan, China — which accounts for about 20% of our exports — may reassess its sanctions (such as the cultural ban, or hallyu ban) based on our diplomatic stance on the Taiwan Strait and alliance modernization. A prolonged Korea–Japan ban could slow China’s economy; combined with tougher disputes in the Taiwan Strait and South China Sea — through which over 90% of Korea’s maritime trade flows — disruptions in shipping would inevitably inflict economic damage.

In short: this may no longer be “just” about ‘if Taiwan happens for Japan, then it happens for Taiwan,’ or “Taiwan contingency equals Japan contingency.” The new Japanese prime minister’s assertive diplomacy is giving both the U.S. and China more leverage to press Korea. As the new Cold War dynamics in Northeast Asia solidify, building peace on the Korean Peninsula and improving inter-Korean relations will become even more difficult. That’s why the return of Northeast Asian geopolitics is deeply unwelcome.

(This article was originally published as a column in Aju News in Korean and translated into English with the help of ChatGPT 5. The views expressed in this article are those of the author(s) and do not represent the official stance of the center.)