South Korea’s vibrant new approach to national security

South Korean President Yoon Suk-yeol has been in office less than six weeks, having been elected by a razor-thin majority. Nevertheless, he already is generating a new sense of optimism about Seoul’s relations with the United States and its wider international profile. 

Unlike his predecessor, the left-leaning Moon Jae-in, Yoon has no reservations about playing up his relationship with Washington. Nor is he inclined to pursue a policy of unreserved reconciliation with Pyongyang. Moreover, Yoon is taking a harder line vis-à-vis  Beijing. And, he seeks to expand and deepen his country’s bilateral, trilateral and multilateral ties ranging from the U.S.-India-Japan-Australia “Quad” to NATO, whose Madrid summit he plans to attend. His approach contrasts with that of Moon, whose foreign and national security policy focused primarily on smoothing relations with the North.

Seoul would like to improve its complicated relationship with Tokyo, in particular. To that end, the new Korean administration is seeking America’s help in enabling it to reach an accommodation with Japan that will allow for closer security cooperation in the face of China’s regional ambitions. The Koreans recognize that there remain outstanding issues with Japan that cannot be easily resolved; otherwise, they would have been some time ago. Nevertheless, Seoul wants to stress the positive regarding its cooperation with Tokyo. On the other hand, as a senior Korean official put it, “It takes two to tango,” and Japan has yet to welcome Korea’s overtures.

It is noteworthy that President Biden visited Korea shortly after Yoon’s inauguration. There is widespread agreement in Korea that the visit was successful. It underscored the close partnership that binds Washington and Seoul and highlighted their shared perception of China’s aggression in the region — as well as the potential for Korea to play an increasing role in ensuring a secure supply chain for the United States that is far less dependent on Beijing. The latter objective highlights the reality that the relationship between Washington and Seoul constitutes more than just one of defense cooperation. 

That relationship has prevented war on the Korean Peninsula for seven decades. The absence of war is not peace, however. The Korean War is not officially over; an armistice still governs relations between the two Koreas. The United States, as the leading element of the United Nations Command — as well as in its role at the helm of the U.S.-Korea Combined Forces Command and as the stand-alone United States Forces Korea — therefore remains a linchpin of South Korean security. The Yoon administration appears interested in a resumption of the broad range of exercises that the Trump administration suspended.

It is expected that North Korea’s seventh nuclear test will take place soon. Seoul seems less exercised about the test than might have been expected. Korea considers a nuclear test a matter for the international community as a whole. Seoul will certainly support any American response to a test, but it is far more concerned about Pyongyang’s missile program; the North’s missiles can now range the entire peninsula. America’s security commitment, therefore, remains as crucial as ever.

South Korea certainly confronts the North with a capable military of its own, but its forces face several serious internal challenges. Perhaps the greatest problem for the Republic of Korea military is the impact of the country’s having one of the world’s lowest birth rates. The Moon administration reduced service time for conscripts from 24 to 18 months. The Yoon government is unlikely to change that policy; the available cohort is simply too small. Instead, the government plans to focus on expanding its high-tech military capabilities, drawn from both foreign sources and the country’s sophisticated industrial base. 

Two aspects of defense modernization have been the subject of considerable debate in Seoul: acquisition of a light aircraft carrier and of nuclear submarines. South Korea has the capacity to build both, but the Yoon administration rightly is concerned about the cost/effectiveness of both potential programs, especially that of the carrier. In a word, the money could be better spent on cyber, space and other advanced technology programs and systems.

In that regard, South Korea is seeking to expand its high-tech cooperation with the United States and other countries in what the government now terms the “Indo-Pacific,” such as Australia, and beyond the region. With a sophisticated defense industry whose products range from some of the world’s finest artillery pieces to highly capable fighter aircraft, South Korea for its part has much to offer.

The Yoon administration clearly has indicated that its policies will mark a major change from those of its predecessor. The opposition party controls South Korea’s legislature, however, and it remains to be seen to what extent that reality will constrain Yoon’s initiatives. Nevertheless, the new government in Seoul promises a reinvigorated relationship with Washington that the Biden administration should not only continue to welcome but also do its utmost to foster.

Dov S. Zakheim is a senior adviser at the Center for Strategic and International Studies and vice chairman of the board for the Foreign Policy Research Institute. He was under secretary of Defense (comptroller) and chief financial officer for the Department of Defense from 2001 to 2004 and a deputy under secretary of Defense from 1985 to 1987.