Three issues that led to hard feelings between the Soviet Union and the United States:

Ideological Differences: The United States and the Soviet Union had fundamentally different political systems and ideologies. The US was a capitalist democracy, promoting individual freedoms and a market-based economy. The Soviet Union, on the other hand, was a communist state, advocating for state control of the economy and a one-party system. These ideological differences led to mutual suspicion and hostility.

Arms Race and Military Competition: The Cold War era saw an intense arms race between the US and the Soviet Union. Both nations built up massive arsenals of nuclear weapons, leading to a state of constant tension and fear of a potential nuclear war. This competition extended into space with the Space Race, further fueling the rivalry.

Conflicting Interests in Europe and Beyond: After World War II, the US and the Soviet Union had different visions for the future of Europe. The US wanted to see democratic governments and open markets, while the Soviet Union wanted to establish communist regimes in Eastern Europe to act as a buffer against potential invasions. This led to conflicts in various parts of the world as each superpower tried to spread its influence.