Answer:
the war in Afghanistan had drained the nation's resources
Step-by-step explanation:
Mikhail Gorbachev is often seen as the person responsible for the breaking up of the Soviet Union, and to some point that is true. The Soviet economy started to stagnate during the 1970's, and one reason for that was that the economy was drained because of the war in Afghanistan. In order to try and boost the economy, Gorbachev decided to make some reforms, most noticeably the Glasnost and Perestroika reforms. Instead of boosting the economy, these reforms actually gave the platform and freedom for the Soviet states to break apart from the Soviet Union, and so it happened at the beginning of the 1990's.