State terrorism refers to acts of terrorism conducted by a state against a foreign state or people, or against its own people. Examples of state terrorism include Mussolini's "Black Shirts", Stalin's "Great Purges", and Hitler's mass extermination of the Jews.
Mussolini's infamous "Black Shirts"
The ultimate form of state terrorism: genocide
Image of one of Stalin's many purges
All four of the totalitarian regimes conducted state terrorism in order to incite fear in their people and to eliminate those who disagreed with the ruling party. They also deployed many police spies throughout their nations to monitor their people and sniff out the heretics.