Summary: why did Cold War tensions develop?

• Ideological differences

  Could be argued that Cold War and breakdown of the Grand Alliance was inevitable due to the ideological differences of the super powers. Eg capitalism allowed freedom including freedom of speech, worship and individual rights. Whereas communism restricted freedoms leading to censorship, state atheism and controls on the rights of citizens to express themselves
• Stalin / Soviets aggression

  US perceived Stalin's actions as aggressive by the USA and their response was containment. Stalin's expansion into Eastern Europe demonstrated this. Eg in Poland Stalin went back on the agreements made at the conferences and supported the Lublin government. Stalins actions in the Berlin Blockade also demonstrated aggression - cutting off supplies to 2.2 million Berliners
• US actions

  Atomic monopoly resulted in the arms race. USA were believed to have used their money to spread their influence / ideology eg through the Truman doctrine and Marshall plan
• Actions of individuals

  - Kennan: detailed his views on the Soviet Union and US policy towards the communist state seeing the USSR as aggressive. Kennan's analysis was key in influencing the policy of containment

  - Churchill called for an alliance between Britain and USA in his iron curtain speech. Stalin saw it as provocative and accused Churchill of being a warmonger and withdrew from the International Monetary Fund and initiated a new field year plan of self strengthening.

  - The Iron Curtain speech and Kennan's telegram led to further hardening of opinions on both sides