During the first half of Lee’s term，he has carried out his electoral commitments by relying on major enterprises to develop economy and trying to address the problem of social polarization by rapid growth in economy. However，having been caught in the simultaneous deterioration of the world’s economy and regional situation on the Peninsula，with economic crisis and tense confrontation between North and South Korea have posed considerable hindrances to the development of national economy，the RK’s recovering economy suffered even more intensified polarization. In this case，the government had to shift to the policy of“Golden-Mean Realism”，changing“Developing Economy，Affinity to Enterprises”to“Constructing Social Justice，Affinity to the People.”Nevertheless，the worsening situation after the Cheonan Incident and the Yeonpyeong Island Incident would inevitably pull the government’s“Golden-Mean Realism”back to a“Right-turn and Conservatism.”Lee’s government，claiming to be expert in economy，would have to meet an unprecedented challenge when issues of security and defense had become overriding.