Elbridge Colby, the U.S. Deputy Assistant Secretary of Defense who previously mentioned South Korea's nuclear armament theory, recently expressed expectations for a more expanded role in South Korea's North Korean defense and defense budget aspects.
Deputy Minister Colby noted on social media platform X on the 1st, following a call between the defense ministers of South Korea and the United States on the 31st of last month, that "South Korea seeks to take on a more proactive role in the aspects of strong North Korean defense and continues to be a role model in defense expenditure."
Deputy Minister Colby stated, "We and South Korea are working closely on the need to modernize the (U.S.-South Korea) alliance in response to the regional security environment," adding, "We will work closely with South Korea to ensure a strategically sustainable alliance prepared to defend against common threats."
These remarks are interpreted as reflecting the Trump administration's expectation that South Korea should shoulder more responsibility in deterring North Korea, amid the United States focusing its capabilities on containing China.
Deputy Minister Colby has consistently maintained that the major security threat facing the U.S. is not North Korea but China. He emphasized that U.S. forces stationed in South Korea should not be solely tied to deterring North Korea but should be organized for contingencies related to China.
He has argued that South Korea must take overwhelming responsibility for the North Korean threat even before his appointment as Deputy Minister. This stems from the judgment that the U.S. lacks the military capability to respond adequately to both China and North Korea simultaneously.
In an interview with a media outlet in 2023, he mentioned that if the continued presence of U.S. troops in South Korea is necessary, that mission should be aligned with South Korea's defense against China. This aligns with the Ministry of National Defense's strategy to operate U.S. forces stationed in South Korea in a way that performs more flexible roles across the Indo-Pacific region.
The positive evaluation of South Korea's defense expenditure is also interpreted as a pressure signal to apply the '5% defense expenditure of GDP' standard, which has been demanded from North Atlantic Treaty Organization (NATO) member countries, to South Korea as well. He previously demanded a similar level of defense expenditure expansion from Japan, causing strong backlash within the Liberal Democratic Party.
The terms 'alliance modernization' and 'response to regional security environment' mentioned by Deputy Minister Colby appear to be directly linked to the restructuring of the role of U.S. forces in South Korea. In particular, the expression 'strategically sustainable alliance' is interpreted as reducing the burden on the U.S. and emphasizing the autonomy of the alliance.
Meanwhile, Colby is assisting Secretary of Defense Pete Hegseth and Under Secretary of Defense Steven Fineberg, playing a key role in the Trump administration's defense policy implementation. He is leading a strategy focused on expanding alliance burdens for countering China and a realist approach, having participated in the establishment of the Trump administration's first defense strategy in 2018. He is currently active as a key figure in the establishment of the defense strategy set to be announced in 2025.