Events such as geopolitical developments in the Southwest Asia region after the Cold War, changes in the global and regional power system and the emergence of new opportunities for the United States on the international stage, naive optimism towards these developments and the failure to adopt a serious and effective strategy to neutralize the country's national security threats, as well as some administrative, economic and executive bottlenecks and inadequacies in the country over the past few decades, led to agreements with Western governments to lift sanctions, one of the most important of which was the Joint Comprehensive Plan of Action or JCPOA. The purpose of writing this research is to examine the historical causes that influenced the formation of the mentality of the two actors (Iran and the United States) in the international arena. The main question of the present research is what historical factors caused the formation of the mentality of the two actors in the international arena from each other and the withdrawal of the United States from the JCPOA and ultimately the military aggression of the United States against Iran? It seems that factors such as; The historical actions of the United States before the Islamic Revolution of Iran, such as its involvement in the coup of August 19, 1953, and years of influence in Iran, the colonization of the mind and the colonial and imperialist approach of the West and the United States, and its support for the Zionist regime and its expansionist ambitions, led to a wave of change in the Islamic Republic of Iran's approach towards the United States and serious reactions against this country. The method of the research is descriptive and analytical, and the data collection method is library and also utilizing scientific resources in cyberspace.