The Breakdown of the US–Soviet Alliance (Cambridge (CIE) IGCSE History)

Revision Note

The Grand Alliance in the Second World War

  • The Grand Alliance was also called the ‘Big Three

    • Its members were the USA, the USSR and the UK

    • They united in the Second World War to defeat the Axis powers of Germany and Japan

  • The members of the Grand Alliance were suspicious of each other:

    • Communism and the strength of the USSR concerned UK and the USA

  • Historians call the Grand Alliance a ‘marriage of convenience’ 

    • The members worked together to defeat a common enemy

    • When they had achieved this, there was nothing to keep the Grand Alliance together

  • After the defeat of the Axis powers by August 1945, the political atmosphere changed

    • ‘Old powers’ like UK and France decreased in power

    •  The new ‘superpowers’ of the USA and the USSR increased in power

Members of the Grand Alliance, 1941-45
Members of the Grand Alliance, 1941-45

The Yalta Peace Conference

  • The Grand Alliance met two years later at Yalta 

    • Yalta was a city in the USSR 

    • The meeting occurred in the final few months of the Second World War

Aims of the ‘Big Three’ at Yalta
Aims of the ‘Big Three’ at Yalta
A list of the agreements made by the Grand Alliance at the Yalta Conference
A list of the agreements made by the Grand Alliance at the Yalta Conference

How Did Yalta Affect the US-Soviet Alliance?

  • The Yalta Conference had a positive impact on the US-Soviet alliance because:

    • The USSR declared war against Japan in August 1945

    • The USSR would gain half of the $20 billion reparations

    • The three main states of the USSR -  Russia, Ukraine and Belarus - joined the United Nations

    • Stalin agreed to free elections in Eastern Europe

The Potsdam Peace Conference

  • The Grand Alliance met a few months later at Potsdam, a city in Germany

  • Several events had happened between the conferences at Yalta and Potsdam:

    • Roosevelt had died and Harry S. Truman replaced him as president

      • Truman wanted a tougher approach to Stalin

    • Clement Attlee replaced Churchill following a general election

    • Germany had surrendered in May 1945

    • The USA had developed a new, devastating weapon - the atomic bomb

    • 51 members had joined the United Nations

Aims of the ‘Big Three’ at Potsdam
Aims of the ‘Big Three’ at Potsdam
A list of the agreements made by the Grand Alliance at the Potsdam Conference
A list of the agreements made by the Grand Alliance at the Potsdam Conference

How Did Potsdam Affect the US-Soviet Alliance?

  • The Potsdam Conference had a negative impact on the US-Soviet alliance because:

    • The Trinity test increased tensions between both countries

    • Stalin wanted harsher reparations against Germany

      • Truman wanted to protect the German economy

    • The USSR’s control over Eastern Europe concerned Truman

      • He believed that Stalin was spreading communism

    • Stalin wanted to keep his Red Army in Eastern Europe as protection against future threats

Worked Example

Why was it harder for the Allies to reach an agreement at Potsdam than it had been at Yalta? 

6 marks

Partial answer:

One reason why it was harder to reach an agreement at Potsdam was a change in leadership (1). Roosevelt had died and was replaced by Harry S. Truman. Truman did not trust Stalin and wanted to take a tougher stance against him (1). As a result, Truman began to stand up against Stalin at Potsdam. The two countries disagreed on issues such as German reparations. Due to Truman’s negative opinion of Stalin and Communism, fewer agreements were made at Potsdam (1)

Examiner Tip

In Paper One, ‘explain why’ questions are worth either six or ten marks. For full marks in this question, an examiner is looking for two fully explained reasons as to why there were disagreements between the USA and the USSR at Potsdam

To complete this answer, you could discuss Stalin’s reaction to the atomic bomb or the presence of the Red Army in Eastern Europe.

The Atomic Bomb

  • The USA dropped two atomic bombs on Japan in August 1945:

    • The first exploded in Hiroshima

    • The second exploded in Nagasaki

  • Both bombs killed roughly 120,000 Japanese civilians

Location of the atomic explosions in Japan
Location of the atomic explosions in Japan
  • The USA had several justifications for using the atomic bombs on Japan:

Why did the USA use atomic bombs?
Why did the USA use atomic bombs?
  • President Truman believed that the use of atomic bombs on Japan would:

    • Persuade Western European countries to support the USA

    • Encourage Eastern European countries to resist Soviet expansion and ally themselves with the USA

Why Did the Atomic Bomb Damage the US-Soviet Alliance?

  • Stalin heard about the success of the Manhattan Project during the Potsdam conference in July 1945

  • After the bombing of Hiroshima, Stalin:

    • Wanted to create a buffer zone between Germany and the USSR

      • The communist countries would protect the USSR from any potential invasions from the West

    • Accelerated the USSR’s atomic bomb project

      • The USSR successfully tested an atomic bomb on 29th August 1949

How did the atomic bombs increase tension between both sides?
How did the atomic bombs increase tension between both sides?
  • The atomic bomb increased Cold War tensions because:

    • Truman wanted to show his power to the USSR

      • He hoped that this would prevent war and protect Eastern Europe from Communism

    • Stalin saw the USA’s actions as aggressive

      • He believed the USA wanted to destroy Communism

      • He became willing to do whatever it took to protect the USSR, including Eastern Europe

The Telegrams and the Iron Curtain

The Long Telegram

  • George Kennan was the USA’s ambassador in Moscow:

    • His opinion on the USSR was highly respected

  • In February 1946, Kennan sent a telegram from Moscow back to President Truman:

    • Its name refers to the length of the telegram

      • It contained around 8,000 words, far more than a typical telegram message

  • The telegram contained Kennan’s assessment of Soviet attitudes towards the USA:

    • Stalin wanted to destroy capitalism as it was a threat to Communism

    • The USA should aim to ‘contain’ the USSR and Communism

    • Peace would not be possible between the USSR and the USA

The Long Telegram, February 1946
The Long Telegram, February 1946

The Novikov Telegram

  • Nikolai Novikov was the Soviet ambassador in Washington:

  • In September 1946, Novikov sent a telegram from Washington back to Stalin:

    • The USSR were aware of the Long Telegram and wanted to make a similar report on the USA

  • The telegram contained Novikov’s assessment of American attitudes towards the USSR:

    • The USA wanted to build up its military strength to achieve world domination

    • Following Roosevelt’s death, the USA no longer wanted to cooperate with the USSR

    • The American people would support a war against the USSR

The Novikov Telegram, September 1946
The Novikov Telegram, September 1946

How Did the Telegrams Impact the US-Soviet Alliance?

  • Both sides believed the other was untrustworthy and planning their destruction

    • The telegrams confirmed these fears

  • The telegrams led to both sides adopting policies toward the other:

How did the telegrams influence US and Soviet policy?
How did the telegrams influence US and Soviet policy?

A British Perspective: Churchill’s ‘Iron Curtain’ Speech

  • Winston Churchill was no longer the British Prime Minister

    • He was still a very influential figure

  • In March 1946, Churchill delivered a speech about the threat of the USSR:

From Stettin in the Baltic to Trieste in the Adriatic, an iron curtain has descended across the continent.

The ‘Iron Curtain’ and divide between East and West
The ‘Iron Curtain’ and divide between East and West
  • The ‘Iron Curtain’ refers to the impenetrable divide between capitalism in the West and Communism in the East

  • Churchill gave the speech in the USA

    • Stalin believed that Churchill’s speech reflected the beliefs of the US government 

  • The ‘Iron Curtain’ speech increased tensions further between the USA and the USSR

    • Both countries built up their military forces, leading to an arms race

Worked Example

Study Source A.

What is the cartoonist’s message? Explain your answer using details of the source and your knowledge

 8 marks 

Source A: A cartoon published in the USA in 1947 by J.N. (Ding) Darling. The figures on the left represent the USA, Britain and France. "Ding" Darling Wildlife Society owns the copyright of "Ding" Darling cartoons.

A satirical cartoon by American cartoonist Ding Darling

Partial answer:

I believe that the cartoonist’s message is that the USSR was wrong to start the Cold War (1). The cartoon shows the capitalist countries of Britain, France and the USA with the United Nations attempting to pull up the ‘Iron Curtain.’ The curtain has a communist symbol (1). This shows that the cartoonist believes that the USSR  is to blame for the divide between capitalism and Communism. The depiction of the United Nations trying with all of its might to lift the curtain shows that, in the cartoonist’s opinion, the USA is still open to better relations with the USSR (1).

Examiner Tip

This style of question in Paper Two needs you to consider:

  • What the message of the source is. Identify the event it is referring to and if it is presenting the event positively or negatively. In this example, the cartoonist had drawn about the Iron Curtain in a negative way

  • Knowledge of the event. This cartoon assumes that the reader knows about the establishment of the UN, the collapse of the US-Soviet alliance and Churchill’s Iron Curtain speech. Add relevant own knowledge of these events to support your answer

  • The purpose of the cartoon. The cartoon was published in an American newspaper in 1947. The cartoon is likely to be biased by blaming the USSR for worsening US-Soviet relations. The cartoon is typical of this, showing how Americans viewed the beginning of the Cold War.

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