Comparison of American foreign policy approach from Obama's diplomatic strategy to Trump's maximum pressure

US foreign policy during the neoconservative rule was based on hard power in dealing with Iran's nuclear program, which was not associated with success and led to an increase in Iran's nuclear power. Obama, who came to power with the slogan of changing and solving the nuclear challenge by using diplomacy, was able to choose a smart policy and reach a nuclear agreement with J.A. Iran to achieve But with the coming to power of Donald Trump, the confrontation between the two countries entered a new phase. Obama's diplomatic solution by adopting a multilateralist approach and focusing on preventing J.A. Iran had pursued nuclear weapons with the aim of building a consensus among countries aligned with the policies of the hegemon (America) towards Iran. On the other hand, Trump's policies are based on a one-sided and confrontational approach based on geopolitical tension and what America was looking for; Revival of American dominance in the form of negation of Obama's theory, non-application of sanctions against J.A. After the JCPOA, Iran's development of militarism in the region and limiting Iran is based on the concepts of power and space according to the hegemon's strategy. Based on this, we try to analyze the reason for the change in the direction of America during the Obama era and the legacy it left behind for Donald Trump with an analytical-explanatory approach and using realistic assumptions.