Communism depended on the west and was sustained by it. Obviously they exported raw materials to purchase the many things they failed to produce themselves incl

Communism depended on the west and was sustained by it. Obviously they exported raw materials to purchase the many things they failed to produce themselves including food. But also particularly, the Soviets had no way to set prices in their centrally planned economy that actually worked, so they kept the show on the road by copying prices from western free market economies. This is one reason the USSR was always lagging behind western economies despite being scientifically advanced. They had to wait for the west to develop products and do price discovery, because GOSPLAN didn't have any way to price things properly themselves.