South Korea is the missing link to the U.S. Indo-Pacific strategy

President Joe Biden’s upcoming travel to South Korea and Japan comes at a critical juncture for U.S. policy in the Indo-Pacific as Washington seeks to strengthen security networks among its allies and partners in Asia and Europe. 

Although Biden’s meeting with his counterparts from Japan, Australia and India at the Quad Summit in Tokyo will likely draw the most media attention, his earlier stop in Seoul will be the real game-changer for the Indo-Pacific strategy. South Korea’s inclusion into the Indo-Pacific framework will have a significant bearing on how security cooperation unfolds among U.S. allies following Russia’s invasion of Ukraine.  

Biden’s meeting with new South Korean President Yoon Suk-yeol will come just 11 days after Yoon’s inauguration. The timing could not be better for Yoon, who campaigned to make a “deeper alliance with Washington…the central axis of Seoul’s foreign policy.” 

Beyond congratulatory remarks, Biden’s stop in Seoul brings to the forefront the missing link to a robust U.S.-Indo-Pacific strategy. Yoon has promised to step up South Korea’s role in the Indo-Pacific, moving away from his predecessor’s more cautious approach to navigating relations between Washington and Beijing.  

For the United States, Biden’s meeting with Yoon gives his administration a chance to welcome a close treaty-ally to the Indo-Pacific fold. South Korea, of course, is not a new player in regional security cooperation. However, until recently, Seoul tended to view the Indo-Pacific strategy primarily through the lens of the bilateral U.S.-South Korea alliance rather than a multilateral perspective. 

In fact, South Korea’s absence from the Indo-Pacific narrative has been puzzling given extremely high public support for the U.S. alliance and very low trust towards China. This perception has not only been felt in Washington but in the Indo-Pacific region itself. 

For example, the Japanese Ministry of Foreign Affairs’ 2021 Diplomatic Blue Book names India, Australia, ASEAN, the United Kingdom, France, Germany and the Netherlands in reference to Indo-Pacific cooperation. South Korea is never mentioned. A prominent Australian foreign policy expert also remarked in a recent conversation that the Koreans have been mostly “outside of the picture” on Indo-Pacific cooperation. This is about to change.  

South Korea’s active engagement in the Indo-Pacific region acts as a force multiplier in building a principled security network — one in defense of the rule of law, freedom of navigation and democratic values. This is possible in three ways.  

First, cautious optimism is growing that Korea-Japan relations will improve. The renewal of bilateral relations carries the potential to strengthen much-needed cooperation in Northeast Asia through U.S.-Japan-Korea trilateral relations. Although the trilateral relationship has persisted (mostly through U.S. prodding) to address ongoing North Korean threats, its expanded role can offer a boost to regional defense and security and enhance coordination on issues such as supply chain shortages related to critical technologies such as semiconductors and batteries.  

Second, South Korea brings to the network of Indo-Pacific partners significant capabilities. South Korea is the 10th largest economy in the world. Less well-known is the fact that it also ranks 10th in global defense spending. The $50.2 billion it spent on defense in 2021 is in the same ballpark as defense spending for France, Germany, and Japan. South Korea is also a sizeable arms exporter, selling weapons such as the K9 Howitzer and the FA-50 light attack aircraft to customers in the Indo-Pacific including Australia, the Philippines, India, Thailand, Malaysia and India among others.  

Third, South Korea’s active participation in the Indo-Pacific will shore up the region’s institutional architecture. In addition to bolstering the U.S.-Japan-Korea trilateral relationship, South Korea may be receptive to strengthening ties with other U.S. allies and partners. An Australia-Korea-U.S. and an India-Korea-U.S. trilateral have been floated by policy experts. Although formal Quad membership is unlikely for the time being, President Biden will likely invite South Korea to participate in the Quad working groups. For its part, South Korea has been a strong proponent of issues central to the Quad such as climate change, COVID-19 vaccines and emerging technologies.    

The Indo-Pacific strategy is a grand strategy for the long haul. Given resource constraints and the reality of a China-Russia axis, the U.S. will need greater support from allies and partners to advance a free and open order. 

By stopping first in Seoul, Biden is recognizing that the Yoon government’s promise to play a larger global role is a major step in that direction.  

Andrew Yeo (@AndrewIYeo) is a senior fellow and  SK-Korea Foundation Chair at the Brookings Institution and professor of politics at The Catholic University of America.