An Introduction to National Security - The Global Consequences Of The Breakup Of The Soviet Union

The 1991 dissolution of the Soviet Union into independent states and its gradual conversion to a capitalist economy brought an end to the bipolar global structure in which most world power rested in the hands of the U.S. and Soviet blocs. What has happened to the balance of power in the world since then is a matter of debate. One theory is that the world has primarily followed an unrivaled U.S. leadership, or "unipolar hegemony." This notion of unipolarity was strongly validated when the United States led a forceful alliance against Iraq during the Gulf War in 1991.

Other international analysts contend that this theory grossly overstates American dominance and that, in fact, the world is much more "multipolar" in nature. A multipolar global order relies on international interdependence, in which each region finds its own optimal power structure. Power, in a multipolar world—whether military, economic, or political—varies from nation to nation, and each uses its strength to fight for survival and dominance.

Joseph Nye, Dean of the Kennedy School of Government at Harvard University and a prominent theorist on international relations, developed yet another model—that of "multilateral interdependence," in which the world power structure can be compared to a three-layer cake. The top military layer is mainly unipolar, since not many states can rival the military might of the United States. The middle economic layer is tripolar, consisting primarily of the strong U.S., western European, and Japanese economies. The bottom layer is made up of transnational interdependence among a number of states. As the idea of interdependence grows, states realize that cooperation is essential to carrying out their policies, especially in the realm of national security.

For the United States this notion is evidenced by the country's participation in various international organizations and regional alliances under the umbrella of "collective security." Collective security is the idea that a group of states sharing common interests should join together against any potential aggression or opposition. A threat to one means a threat to all. This is not a recent phenomenon and can be traced back centuries to ancient times. In the early twenty-first century, the United Nations (UN) and the North Atlantic Treaty Organization (NATO) are the primary bodies through which the United States engages in collective security. Bilateral military alliances (between the United States and one other country) or multilateral alliances (involving several countries) are other avenues for collective security.