The policies formed by US leadership play a vital role in establishing US hegemony all over the world. The foreign policy of a state made according to the national interest. A rational decision of a leader plays a vital role in the effectiveness of the foreign policy. The challenges faced by Barack Obama in 2008 were somehow different from the challenges faced by Trump in 2016. The comparative analysis of both foreign policies would make it easy to determine the right and wrong decision taken by both leaders. The changing circumstances of the world would be identified through this research paper. The world is moving towards multipolarity, and somehow the decisions taken by Trump after his incumbent of office had the worst impact on US foreign policy because Trump was trying to isolate the US from world affairs, including trade and security.