In December 1988, Gorbachev announced that ideology should play a smaller role in foreign affairs, meaning that Soviet troops would no longer intervene in Eastern Europe to support communism.
The fall of the Berlin Wall was preceded by public demonstrations in many East German cities, especially Leipzig, where the East German leader, Eric Honecker, received no assurances from Mikhail Gorbachev that he would support any attempt to deal with these protests using force.
The fall of the Soviet Union led to the end of the Cold War as the Soviet Union no longer existed and there was no ideological conflict between East and West.
The meeting of Bush and Gorbachev in December 1989, the Malta Summit, declared an end to the Cold War, paving the way for the collapse of the Warsaw Pact, which was formally dissolved in July 1991.
The Soviet Union became the Commonwealth of Independent States in January 1992, with many Soviet states seceding and becoming independent states, including Ukraine, Estonia, Latvia, and Lithuania, as well as Asian Republics such as Kazakhstan.
At the Strategic Arms Reduction Treaty (START) (1991), the USA and Soviet Union agreed to reduce nuclear warheads by about a third, with an additional undertaking to reduce them further.