The Secret Police in the Soviet Union in the era of Stalin 1928-1953

The Soviet union was foundation on the security bases and the net of intelligence, which set the Communist system in the country after Bolshevik Revolution.
It was the first of a succession of Soviet state security organizations. It was created on December 20, 1917, after a decree issued by Vladimir Lenin, and was subsequently led by Felix Dzerzhinsky.
after stalin became the first secretary, and adopt the new economic strategy, the power of secret police were raised up to fought the counterrevolution, which became follow up the army ,economic plan, religious life, and observed the enemy outside of the Soviet Union, such as "trust operation", Shakhty trial and Dekulakization
the secret policy became the most powerful in era of  Yezhov, He was head of the NKVD, in the 1937 during the most deadly period of Stalin's Great Purge, after presiding over mass arrests and executions, of millions of people throughout the Soviet Union or sent to Gulag  Outside the framework of the law and without trials.
Lavrentiy Beria  became the head of NKVD  ,his leadership of the organization marked an easing of the repression begun under Yezhov. Over 100,000 people were released from the labour camps, and foundation the special department inside the army named SMERCH.
In 1943 separated the secret police from the Interior Ministry and create independent of the Ministry, is responsible for monitoring all the economic activities and the gulag, and after World War II.
after World War II and join a lot of Eastern European countries to the Soviet Union, became the device follows the acts of sabotage and resistance, espionage and functioning of the economy within the countries joined the Soviet state.

the result of this terror, it is  became the main reason of suffering  of the people , and control the feature of soviet people , that carried inside the collapse of the Soviet union.