Final answer:
Mikhail Gorbachev's internal reforms, including glasnost and perestroika, accelerated the collapse of the Soviet Union. His decision to not intervene militarily in Eastern Europe during the revolutions of 1989 also contributed to its fall.
Step-by-step explanation:
The fall of the Soviet Union can be attributed to a combination of factors, but one could argue that Mikhail Gorbachev played the most significant role in its downfall. Gorbachev, as General Secretary of the Communist Party of the Soviet Union, implemented reforms such as glasnost (openness) and perestroika (restructuring) in an attempt to modernize the Soviet economy and political system. However, these reforms inadvertently accelerated the collapse of the Soviet Union. For example, Gorbachev's policies of increased political openness allowed for the rise of nationalist movements in Soviet republics, leading to demands for greater autonomy and ultimately independence.
Furthermore, Gorbachev's decision to not intervene militarily in Eastern Europe during the revolutions of 1989 also contributed to the fall of the Soviet Union. For instance, when the Berlin Wall fell, Gorbachev chose not to use force to maintain Soviet control over East Germany. This act signaled to other Eastern European countries that the USSR would not intervene to suppress popular uprisings, paving the way for their own revolutions and the dismantling of the Soviet sphere of influence.
While Ronald Reagan's policies, such as the Strategic Defense Initiative (SDI), put economic pressure on the Soviet Union, it can be argued that the internal reforms implemented by Gorbachev had a more significant impact on the collapse of the Soviet Union.
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