Explain how soviet declination of the World Bank illustrated a fundamental conflict at the heart of the Cold War. Make your answer one sentence.

The Soviet Union's declination of the World Bank demonstrated the communist belief in self-sufficiency and rejection of capitalist institutions, highlighting the fundamental conflict between communism and capitalism at the heart of the Cold War.

shorter

The Soviet Union's refusal to join the World Bank showcased the clash between communism and capitalism during the Cold War.