Photo: IC

Fraying relations between Japan and South Korea since 2018 have reached a nadir - the lowest point since 1965 when the two countries normalized diplomatic ties. Relations have taken a beating over three sensitive flashpoints - the "comfort women" issue, compensation for South Korean people forced to work for Japanese firms during WWII and a warship radar lock-on incident. Japan has recently tightened restrictions on its export of high-tech materials to South Korea. The Japanese Ministry of Economy, Trade and Industry said that the "relationship of trust [between the two sides] has been markedly damaged."

Undulations in Japan-South Korea relations after the Cold War are not new. But this time the US seems to have no interest in playing peacenik between its two important allies in Northeast Asia. Some believe this can lead to long-term antagonism between the two countries. David Stilwell, the US assistant secretary of state for East Asian and Pacific Affairs, told Japanese media that the US has no plans to mediate the spat, but would only encourage both sides to focus on key regional issues and in particular North Korea.

Theoretically, if Japan, South Korea and the US can form a trilateral alliance to replace the current Japan-US and South Korea-US alliance, the US military presence in East Asia will be buttressed. The three countries will then form a NATO-like collective security structure. 

Washington has been stressing that strategic interests are above historical issues and territorial disputes in its relations with Tokyo and Seoul. During the Obama administration, the US used to play the role of mediator between Japan and South Korea. For example, in a bid to strengthen trilateral relations, former US president Barack Obama held a meeting in The Hague in 2014 with Japanese Prime Minister Shinzo Abe and then South Korean president Park Geun-hye. 

But why is the administration of Donald Trump not interested in getting involved in the Japan-South Korea spat? How will this affect the US security structure in Northeast Asia?

First, the Trump administration has broken with previous US policies on North Korea. In opening up a direct dialogue with Pyongyang, Washington has forsaken the tradition of using North Korea to strengthen Japan-South Korea-US cooperation. Trump hoped to make a breakthrough on the Korean Peninsula nuclear issue and scaled down joint military exercises with South Korea. 

China, South Korea and Russia are all trying to persuade the US to lift economic sanctions on North Korea, while Japan has been emphasizing the issue of North Korea's abductions of Japanese nationals. Thus Japan and South Korea have different expectations for Washington's policy toward Pyongyang. Therefore, for Washington, intervening in Tokyo-Seoul relations may serve neither side.

The nuclear crisis on the Korean Peninsula has been the only pivot for political and security cooperation between Japan, South Korea and the US. If such pivot is shaken, there will be fundamental changes in Northeast Asia's security situation. During the latest round of diplomatic flurry on the Korean Peninsula, North Korea has already had direct talks with four out of six members of the Six-Party Talks, leaving Japan behind. This has added to Japan's strategic anxiety. On the one hand, Washington may reassure Tokyo to stabilize their alliance; on the other hand, it may start diplomacy with Pyongyang at the appropriate moment.

Second, the US failed to strengthen Japan-South Korea relations to set up a trilateral alliance. Although the US tried to promote a quasi-trilateral alliance and Tokyo and Seoul reached agreements on intelligence sharing, Japan-South Korea defense cooperation could not be forged because of historical problems, political distrust and territorial disputes. Besides, a trilateral alliance means the integration of the three countries' military. This will trigger strong opposition from North Korea, China and Russia, leading to regional tensions as there has already been much unease in US relations with China and Russia. Hence the best choice for Washington would be to maintain bilateral alliances with both Seoul and Tokyo.

Third, periodic tensions in Japan-South Korea relations occur because of historical issues and the power change in Northeast Asia. Washington cannot do much to help. With China's rise and South Korea's vaulting economic development after the Cold War, South Korea's economy has become more closely linked with that of China although the US and South Korea are still allies. South Korea will have to think more from China's perspective and that of its own, and less from that of US and Japan. For the US, intervening in historical and territorial issues between Japan and South Korea means it has to choose sides. Thus Washington has chosen not to get involved.

This indicates the weakening control of the US on its two Northeast Asian allies. In other words, Japan and South Korea now have more strategic independence. Indeed, this may whip up nationalism in the two countries and affect the situation in the region. The two countries' strategic thinking used to be centered on Washington because of the alliance system. Japan and South Korea lack mutual trust and motivation to develop bilateral relations, and have depended too much on US mediation.

But challenge also leads to creativity and opportunity. For the US, developing a more compatible security structure in Northeast Asia means it can maintain its long-term interests and presence in the region. Meanwhile, it is time for Japan and South Korea to be less dependent on the US and find their way out.

The author is an associate professor of National Niigata University Japan and a senior fellow at the Institute of Advanced Area Studies and Global Governance, Beijing Foreign Studies University. opinion@globaltimes.com.cn