During the Cold War era, South Korea anchored its security policy mainly to deterrence against the North Korean threat. The main functions of the ROK-US alliance were limited to the Korean Peninsula, leaving the regional role of the alliance rather underdeveloped. However, with the rapid emergence of South Korea as an economic middle power successfully democratized and with the transformed nature of the regional and global environment, things have changed. Its national strategy has been reshaped beyond the scope of the peninsula and begun to be concerned with broader security architecture. This raises questions on how to adjust the alliance for a wider context.