Abstract: The new leaders of Soviet Union actively called for peaceful coexistence with capitalist countries after 1953, and there was a relaxation of tensions between East and West. Syngman Rhee worried that U.S. would abandon the Republic of Korea, as a price of buying peace. Therefore, he provoked a dispute over the Neutral Nations Supervisory Commission to create tension. The Eisenhower Administration believed that unilateral actions by ROK most likely started hostilities which would get U.S. involved. For this reason, U.S. used tactics of appeasement and pressure against Rhee. On June 9, 1956, the U.N. command removed the NNSC personnel from ROK and the dispute was settled. The dispute over NNSC between U.S. and ROK tells us that the main reason for U.S.ROK crisis of confidence is the difference between global considerations of the U.S. and local considerations of the ROK. The U.S. often examines closely the Korean Peninsula problem from an Asian or even global angle, and isn’t willing to be entrapped by unilateral actions of ROK, and the ROK always judges U.S. global and Asian policies on the basis of its national security interests and worries about being ignored or even abandoned by U.S.