Afghanistan, as one of Iran's strategic neighbors and part of a shared civilizational sphere, possesses significant geopolitical and cultural capacities for the formation of regional cooperation; however, the persistence of internal instability and the rivalry of regional and trans-regional powers have hindered the effective utilization of these capacities. An analysis of Afghanistan's situation indicates that the roots of instability lie in four main crises—legitimacy, identity, participation, and distribution—which have prevented the consolidation of the state-nation, hindered national cohesion, and rendered security fragile. At the regional level, Afghanistan's position at the crossroads of East-West and North-South connectivity has transformed it into a buffer zone and a focal point for the intersecting interests of actors such as the United States, Pakistan, India, China, Russia, and Saudi Arabia; consequently, the persistence of insecurity, the spread of extremism, and the rise in drug production have direct consequences for regional security. Iran-Afghanistan relations, despite historical commonalities and high economic potential, have also been influenced by third-party factors and tension-inducing issues such as the American presence, Saudi influence, the Helmand River water rights, migration, and Iranophobia. Proposed strategies emphasize supporting a powerful and inclusive central government, conducting pathology of regional cooperation and bilateral relations, centering economy and transit, strengthening public and academic diplomacy, and providing enforcement guarantees for commitments and memoranda of understanding to develop sustainable cooperation.