Analyzing US foreign and security policy towards Afghanistan, as one of the most important issues in international relations and security studies, requires understanding the factors influencing policymaking. One of the important factors is the role of security experts and their influence on shaping US security policies, which can be examined based on the Paris School security theory. This research seeks to answer the question: How have security experts in US foreign and security policy towards Afghanistan influenced the country's strategic decision-making during the years 2001 to 2021? It seems that security experts, by providing intelligence analysis, developing counterterrorism strategies, and influencing decision-making processes in US policymaking institutions, have played a decisive role in shaping the country's foreign and security policy towards Afghanistan during the years 2001 to 2021. More importantly, the research findings show that by highlighting security threats and influencing public opinion and policymakers, these experts propose policies that are consistent with strategic goals and interests, and these policies change over time in line with security priorities. These findings indicate the importance of interaction between security structures and the individual role of experts in security policymaking.