The situation in East Asia is changing dramatically, increasing the importance of a concerted approach by U.S. allies and friends. It is significant, therefore, that the U.S. and South Korean leaders successfully confirmed continued cooperation.

After Prime Minister Suga Yoshihide, who visited the U.S. in April, South Korean President Moon Jae-in became the second world leader to meet U.S. President Joe Biden in person. The Biden administration emphasizes the importance of the Asian region; it has likely chosen to reinforce ties with its close ally as the first step.

During the meeting, the two leaders shared deep concern about North Korea and agreed to aim for denuclearization of the Korean Peninsula through a “realistic approach.”

Close to 30,000 U.S. troops are currently stationed in South Korea, concentrated in the area between Seoul and the Demilitarized Zone. The U.S. is worried that lack of coordination between the American and South Korean militaries could gravely undermine the two nations’ response to North Korea’s accumulation of nuclear weapons.

In the face of the increasing Chinese pressure on Taiwan, the U.S. and South Korea stressed the importance of maintaining peace and stability in the Taiwan Strait in their joint statement, an accommodation made by Moon to the determined U.S. President. While Japan should closely monitor South Korea’s future approach, it has become clear, the U.S. intends to ensure trilateral coordination with Japan and South Korea to address the Taiwan issue in particular. 

On the same day as the leaders’ meeting, the South Korean government announced that major South Korean corporations, such as Samsung Electronics and Hyundai Motor Co., will invest about 4 trillion yen in the U.S. This is in line with the U.S. economic security plan to establish supply chains independent of Chinese influence amidst the U.S.-China conflict over semiconductors.

The U.S. alliance strategy has been affected by the prolonged dispute between Japan and South Korea, which was fueled by Japan’s tightening of export controls on goods shipped to South Korea, including materials for semiconductors, as well as by the South Korean boycott of Japanese products that followed. The two countries’ dispute originally began with the South Korean judiciary’s ruling on a case involving war-time requisitioned labor. Normalization of relations between the two countries is urgently called for.

There is a possibility that the Moon administration will lean further toward China and North Korea to secure Moon’s political legacy ahead of the end of his presidential term within one year from now. As the stage of global power game shifts to East Asia, cooperation among Japan, the U.S., and South Korea has become even more important for the security of the region.