The Role of Obama and Trump's Foreign Policy on International System Structure

Obama's announced policies and approaches despite emphasizing on economic coopera-tion’s, new regional and international capacity buildings, democracy, human rights, multilateralism and Emphasis on soft power, included realist principals and results while Trump's unilateral, aggressive and beneficial approaches emphasize on American values and national interests as the main factors influencing his administration foreign policy. This article with using explanatory research method, is considering to have study aboutthe role of Obama and Trump's foreign policy on International System Structure. The results of the study indicate that Obama's foreign policy despite adhering realistic principles,with paying special and smart attention to internal interests and military pow-er, increased the importance of diplomacy and soft power, functional capabilities of in-ternational institutions and organizations, avoided preventive wars and emphasized on multilateralism, while Trump's foreign policy had results like increasing the importance of hard power, growth of Current international order brittleness, tendency towards na-tional economy and global economic tensions, diminishing the Importance of diplomacy and negotiation, decline in the importance of international law and international institu-tions, growth of regional economic exchanges, facilitating the process of moving to-wards a multipolarorder, increasing pessimism to future security trends, formation of new international and regional arm races and finally is increasing the level of disputes and instability in the current international system structure.