The ancient Chinese were not willing to share the art of silk production with other cultures. It was a closely guarded secret for a long period. Though silk was traded through the silk route, the method of its production was not known to the world.
Other cultures assumed it also came from a plant, like other fabrics. Any person who tried to reveal the secret was given the death penalty.
cause of tension was that the Soviet Union was trying to spread communism. The U.S. was against communism and they took leadership of containment policy. The Containment policy was the U.S. approach to trying to prevent communism spreading.