South Korea is facing a nightmarish international environment, wholly unexpected as recently as 2015. Then the country was riding high in its foreign policy agenda: trustpolitik leading to a bonanza, “honeymoon” with Xi Jinping, best relations ever with the United States, a “comfort women” agreement with Japan, and, ahead, the Northeast Asian Peace and Cooperation initiative aimed at bridging the region’s divides. In 2016, the letdown was significant, albeit limited. China was angry that Seoul had agreed to THAAD after North Korea’s tests, but the United States and Japan were upbeat about relations, as the agenda was narrowed with emphasis on coordination in the face of the growing threat. By the end of April 2017, the situation had deteriorated sharply. China was angrier than ever, Japan was again being targeted by Seoul, and, abruptly, Donald Trump decided to threaten Seoul to pay for the THAAD deployment and renegotiate KORUS FTA. Is the way forward to appeal directly to North Korea and yield to China’s demands, or to find a pathway for rebuilding ties with the United States and Japan, recognizing that alienating Japan now would reverberate in poorer relations with Washington? Given the essential role of the ROK-US alliance, this article starts from the premise that the alliance triangle is what takes priority.