In fact the countries need a secret service to contribute to directing their foreign policy in accordance with the methods and procedures required by the necessity of defending their interests. These motives have encouraged successive American administrations, especially since the First World War and to this day to develop the process of obtaining information. A spy whose mission is to uncover competitors' plans and reorient them politically and economically at first, but later included various fields and aspects, including social and cultural, and became an effective tool in uncovering secrets through a network of agents, citing the pretext of preventing and stopping any counting of the potential on national security. This study sheds light on the process of the emergence of this body and the stages of its formation, and what are the necessities that prompted successive US administrations to support it but secretly, where the stages of its development were not by chance as some understand it. The United States was always in need of information gathering, and this was an obsession inherited by decision-makers in US policy, and away from US concerns and geographical isolation. It was very willing to know what is happening in the outside world and harnessing its interests through methods and means to ensure the success of its policy in dealing with those countries. Thus, the adaptation of this secret apparatus to the stages of political developments imposed by the international arena was analysed; and when the issue of expelling the country and avoiding its interests and national security of wars and disasters falls on the US administration, which is directly responsible for achieving security and economic welfare, had to search for a special mechanism in the collection and analysis of positions and harnessing them to serve their interests.