The Breakup of the Soviet Union and the Bush -- Yeltsin Agreement
Then, after all its decades of struggle with the United States, the Soviet Union ceased to exist. The landscape of the nuclear age was transformed overnight.
The Soviet Union consisted of fifteen republics: Armenia, Azerbaijan, Belarus, Estonia, Georgia, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Moldova, Russia, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan. Of these fifteen republics, nine signed a treaty forming the Commonwealth of Independent States in December 1991 when the Soviet Union broke up. Georgia, Estonia, Latvia, and Lithuania did not sign, and Azerbaijan and Moldova failed to ratify the treaty. However, in the fall of 1993, both Georgia and Azerbaijan joined.
Shortly after the breakup of the Soviet Union, the Chechen-Ingush Autonomous Soviet Socialist Republic of the Russian Federation declared its independence. The republic occupied what was regarded as a strategic position, and in the months that followed Yeltsin intervened in Chechnya, first in a covert operation and then with Russian troops. After many months of struggle, Russia finally agreed to Chechen independence. So, at the present time, the Commonwealth consists of Russia, Kazakhstan, Ukraine, Belarus, Armenia, Uzbekistan, Turkmenistan, Kyrgyzstan, Tajikistan, Georgia, and Azerbaijan.
It is important to understand that the Commonwealth is not a unitary state. It is, in fact, a confederation of independent states. Although its permanent shape and division of responsibilities are far from being final, the Commonwealth will presumably end up being responsible for defense and foreign affairs and possibly some aspects of trade and commerce, while the members will retain sovereignty over all other matters.
The first question is why. What were the fundamental causes of the Soviet breakup? The second question is how this new line up will affect the problem that nuclear weapons pose.