This article provides a historical account of the U.S.-Iran nuclear cooperation, spanning from its inception during President Eisenhower's "Atoms for Peace" initiative in 1957 to the contemporary diplomatic challenges centered around the Joint Comprehensive Plan of Action. The Joint Comprehensive Plan of Action, often referred to as the Iran Nuclear Deal, is a landmark international agreement aimed at addressing concerns about Iran's nuclear program. The Plan was negotiated and signed on July 14, 2015, between Iran and the P5+1 group of countries, which includes the United States, the United Kingdom, France, Germany, China, and Russia, plus the European Union. The article critically assesses the objectives of the Plan and the robust dispute resolution mechanism embedded within it, with a particular focus on the pivotal role of the United Nations Security Council in endorsing, enforcing, and safeguarding the JCPOA. Furthermore, it scrutinizes the Security Council's limited ability to respond to the unilateral withdrawal of the US, highlighting the challenges in enforcing international agreements when influential nations act independently. The complexities and implications of the Security Council's functions in upholding international norms are central to this analyses.