The Soviet Union fell apart on December 1991. But in reality the struggle for its dissolution goes on till today and only in its context can be explained the conflicts in Georgia and Ukraine.
Both Ukraine and Uzbekistan are the two most important states in this protracted war which is a “war” for domination in Eurasia. Brzezinski was the most outspoken proponent of this strategy, even if lately he was obliged to retreat a little bit from these designs. Here are two old texts explaining this strategy: