The fall of the Berlin Wall and the subsequent end of the Cold War radically transformed the international structure such as had existed since the end of World War II. That war's conclusion resulted in the establishment of what was known as a "bipolar" international structure, in which global affairs were influenced, if not defined, by the stand-off between the two superpowers, the United States and the Soviet Union. This bipolar structure contrasted with the multi-polar structures that existed in previous eras, in which many seats of power existed alongside one another and in which international diplomacy involved constant maneuvering of powers among one another for preservation and advantage. The bipolar structure was, in a way, more stable than the multi-polar structures, but the existence of large nuclear stockpiles by each of the two superpowers meant that any major breakdown in international order could end in the deaths of tens of millions of people.
With the end of the Cold War, the bipolar structure that defined the era no longer predominated, replaced by the emergence of new powers, mainly China (in both the economic and military spheres) and significantly by the growth of what was initially known as "asymmetric threats" to regional and global stability. These asymmetric threats included terrorism, insurgencies, and localized wars, such as would break out in the former Yugoslavia. The fall of the Berlin Wall, then, marked the end of the Cold War but the beginning of a more complex international structure, featuring more diverse threats to international stability.