The demise of the Soviet Union and the end of the bipolar system affected the geopolitics of the glob. One of the main features of the new world system is the importance of the world economy; accordingly, any power that dominates the Persian Gulf, with its enormous energy resources, would dominate the world. Yet, Central Asia, with its energy resources and strategic location, has attracted the powers attention. Under the new circumstances, the United States has tried to play an influential role in both regions. Here the main question is: which region is more important in US foreign policy, the Persian Gulf, or Central Asia? The paper concludes although Central Asia has a special role in US global policy, particularly after the 9/11 events, the Persian Gulf, for its greater amount of energy and crucial geopolitical position, as a new “heartland” or “center of the center” contains long-identified vital US national interests and security more than any other region.