External factors

There were another factors apart from Gorbachev's actions that lead to the collapse of Soviet control.

• The war in Afghanistan

Originally it was an attempt to take control of Afghanistan, but they Afghan militia engage the Soviet in what became a guerrilla-style war in 1979. The war badly overstretched their economy and demoralised their military. The war led to widespread condemnation by other countries and pressure to withdraw.

• The role of the USA

Reagan (president from the USA) and Gorbachev encouraged an end to the Cold War. Both signed treaties to limit nuclear weapons and also encouraged people-led movements in Eastern Europe. Moreover USA increased the "arm race" and the Soviet Union could not respond respond to it, so they needed to securing peace through diplomacy.