In 2022, several factors including the inauguration of South Korean president Yoon Suk-yeol and a major uptick in North Korean military provocations helped improve bilateral relations between South Korea and Japan and boost trilateral cooperation between South Korea, Japan, and the United States. This paper examines newfound opportunities for trilateral cooperation in light of shifting domestic politics, increased external threats, and a growing awareness across the three governments that their national interests are better served by working together within the Indo-Pacific. Although the opportunities for enhanced cooperation are as ripe as ever, several challenges still loom ahead regarding U.S.-Japan-Korea (UJK) trilateral relations and the broader goal of eliminating North Korea’s nuclear and missile threat. Nevertheless, for South Korea, UJK relations remains not only important for addressing North Korean threats, but in providing a major platform for cultivating deeper roots to cooperation in the Indo-Pacific region. Thus, every effort should be made to strengthen and expand UJK trilateral relations moving forward.