Ideological differences: The Soviet Union was a communist state, while most Western countries were capitalist. The Soviets saw Western influence as a threat to their political system and ideology. They feared that Western ideas and values would undermine the communist system and lead to the spread of democracy and capitalism.
Security concerns: The Soviet Union was a closed society and was concerned about its own security. The Soviets were worried about Western espionage and feared that Westerners would gather intelligence about their military installations and plans. They also wanted to prevent Westerners from spreading anti-Soviet propaganda.
Control of information: The Soviet Union tightly controlled information and media within its own borders. They wanted to prevent the spread of Western ideas and culture, which they saw as harmful to their society. By limiting access to Western peoples, they could ensure that their citizens would not be exposed to these influences.
Cold War tensions: The Cold War was a period of intense rivalry and conflict between the Soviet Union and the United States. This conflict led to mutual distrust and suspicion between the two superpowers. The Soviets were wary of any contact between their citizens and Westerners, fearing that it would lead to increased tensions and hostility.