Hello, my name is Mr. Williams, and I'm going to be your history teacher today.

This lesson is part of a series on the origins of the Cold War, and in today's lesson, we're going to be learning about the impact of the atomic bomb on US-Soviet relations.

I'm really looking forward to teaching you today, so let's get started.

Our lesson today will be split into three parts.

In the first part of our lesson, we're going to be learning about the events that led the Americans to become the first country to develop an atomic bomb, and how the USA then used the atomic bomb against the Japanese cities of Hiroshima and Nagasaki at the end of the Second World War.

The timeline on the screen provides an overview of the key events that we'll be learning about in this first part of our lesson.

In 1942, during the Second World War, the USA with support from Britain and Canada began a huge, top secret research and development project known as the Manhattan Project.

The aim of the project was to develop nuclear weapons, specifically the atomic bomb, before Nazi Germany or any of the USA's other enemies were able to do so.

Although the USSR was fighting alongside Britain and the USA as part of the Grand Alliance, the USA attempted to keep their efforts to develop the atomic bomb a secret from their Soviet allies.

Despite this, the USSR managed to discover a lot about the Manhattan Project through espionage.

On at least three separate occasions, Soviet spies penetrated security at Los Alamos, New Mexico, where the bomb was being developed.

The fact that the USA did not tell the USSR about the Manhattan Project and that Stalin mounted a major espionage operation on a wartime ally highlights the lack of trust that existed between the USA and the USSR, despite being at the height of their wartime cooperation.

On the 16th of July, 1945, the USA carried out the Trinity Test, successfully detonating an atomic bomb in the New Mexico Desert.

The next day, at the start of the Potsdam Conference, President Truman informed a furious Stalin that the USA was in possession of nuclear weapons.

It was not long before they were used.

Let's take a moment now to check your understanding.

On the screen is a question.

What was the aim of the Manhattan Project? I want you to take a moment now to explain your ideas to your partner.

Pause the video and press play when you're ready to see a model response.

Okay.

Thank you.

I hope those discussions were useful.

Your response could have included: The aim of the Manhattan Project was for the USA to develop nuclear weapons, specifically the atomic bomb before any of their enemies.

Let's do another quick check for understanding.

What name was given to the first successful test of the US atomic bomb on the 16th of July, 1945? Was it the Alpha Test, the Manhattan Test, the Omega Test, or the Trinity Test? Pause the video now and press play when you're ready to see the correct answer.

Okay, the answer is the Trinity Test.

Very well done if you got that correct.

Okay.

Let's do another quick check for understanding.

There's a statement on the screen and it says, "Before the Potsdam Conference, Stalin knew nothing about American attempts to develop an atomic bomb." Is this statement true or false? Pause the video now and press play when you're ready to see the correct answer.

Okay, very well done if you said that the answer was false, but we need to be able to justify that response, so on the screen there's two statements.

The first says: "The USA and the USSR were allies, so Stalin knew about the Manhattan Project from the beginning." And the second statement says: "Stalin used espionage to find out about the Manhattan Project." Which of these statements best justifies why the original statement was false? Pause the video now and press play when you're ready to see the correct answer.

Okay, well done if you said that the correct answer was statement B.

Stalin did not know about the Manhattan Project from the beginning, however, he was able to find out about it using espionage.

On the 6th of August, 1945, an American B29 bomber, the Enola Gay, dropped the world's first atomic bomb over the Japanese city of Hiroshima, and on the 9th of August, a second atomic bomb was detonated over the Japanese city of Nagasaki.

The blast at Hiroshima had the explosive power of 15,000 tonnes of dynamite, and the temperature at the centre of the explosion reached 300,000 degrees centigrade, 50 times hotter than the surface of the sun.

In total, it is estimated that over 120,000 Japanese civilians were killed by the two bombs.

Some people were vaporised instantly by the blast while many others died much later from horrendous burns or radiation sickness.

Let's take a moment now to check your understanding.

On which two Japanese cities did the USA drop atomic bombs? Was it Hiroshima, Nagasaki, Tokyo, or Yokohama? Select two.

Pause the video now and press play when you're ready to see the correct answer.

Okay, very well done if you said that the correct answer was Hiroshima and Nagasaki.

Let's do another quick check for understanding.

On the screens, there's a question that says, "How many people were estimated to have been killed by the atomic bombs dropped on Hiroshima and Nagasaki? Was it A: 12,000, B: 22,000, C: 120,000, or D: 220,000? Pause the video now and press play when you're ready to see the correct answer.

Okay, well done if you said C.

The correct answer was 120,000 civilians were killed by the two atomic bombs.

We're now ready for the first practise task of this lesson, which is split into two parts.

In this first part, there are some events listed on the screen and I want you to put them in the correct chronological order.

Pause the video now and press play when you're ready to see the correct answer.

Okay, well done for your hard work on that task.

You were asked to put some events in chronological order, and this is the correct order.

The USA began the Manhattan Project.

The USA successfully tested the first atomic bomb.

Truman informed Stalin that the USA had atomic bombs.

The USA dropped atomic bombs on Hiroshima and Nagasaki.

Japan surrendered.

Very well done if you got that correct.

Let's move on to the second part.

In the second part of this practise task, I want you to write down whether you agree with Aisha.

Aisha has said, "The relationship between the USA and the USSR was tense and they were suspicious of each other before the USA used atomic bombs against Japan." Do you agree? I want you to explain your answer.

Pause the video now and press play when you're ready to see a model response.

Okay, well done for your hard work on that task.

You were asked whether you agreed with Aisha that the relationship between the USA and the USSR was tense and they were suspicious of each other before the USA used atomic bombs against Japan.

Your answer could have included: "I agree with Aisha that US-Soviet relations were tense before the USA used atomic bombs against Japan.

This is shown by the fact that the USA kept the Manhattan Project secret from the USSR.

It is also shown by Soviet attempts to find out what was happening through espionage and Stalin's furious response when he was informed at Potsdam." Very well done if your answer looked something like the model answer on the screen.

Let's move on now to the second part of our lesson where we're going to be learning about the Soviet response.

The timeline on the screen provides an overview of the key events that we'll be learning about as part of this section of the lesson.

The American decision to use the atomic bonds on Japan was a deeply controversial one.

Japan surrendered on the 15th of August, 1945.

Truman and many others argued that this only happened so quickly because of the destruction of Hiroshima and Nagasaki.

On the other hand, some historians argue that the USA could have won the war without choosing nuclear weapons.

Truman had already pushed back the start of the Potsdam conference to take place after the atomic bomb had been successfully tested.

Historians who argued that the attacks on Hiroshima and Nagasaki were not necessary claim their main purpose was to demonstrate American power, give confidence to countries in Western Europe that the USA could protect them, and establish a stronger bargaining position with the USSR.

Stalin was certainly of this view and commented, "A-bomb blackmail is American policy." Let's take a moment now to check your understanding.

I want you to read Laura's view about the American decision to drop atomic bomb on Hiroshima and Nagasaki.

Why would some people disagree with her? Okay, well done for your hard work on that question.

You were asked why some people would disagree with Laura, and you could have written, "Some people believe that the USA dropped the atomic bombs to demonstrate American power to the world, especially the USSR." And you could also have written, "Some people argue that Truman wanted to intimidate the USSR." Very well done if you got that correct.

If Truman believed that having the atomic bomb would make it easier for the USA to persuade the USSR to give eastern European countries more freedom, he was wrong.

In fact, it had the opposite effect.

Stalin wanted to show that the USSR could not be intimidated, and he took an even harder line in pursuit of Soviet objectives.

More determined than ever to ensure the security of the USSR, Stalin remained convinced that the best way to do this was to establish a buffer zone of friendly communist countries between Germany and the USSR's western border.

In 1945, the Soviet Union was already developing its own atomic bomb, with Stalin declaring, "Hiroshima has shaken the world, the balance has been destroyed.

That cannot be." On the 29th of August, 1949, the USSR successfully tested its own atomic bomb, just four years after the USA.

On one hand, the development of the atomic bomb dramatically increased tensions between the USA and the USSR, as both countries were now in possession of weapons that could destroy entire cities and kill hundreds of thousands of people.

On the other hand, the terrible consequences of using an atomic bomb may have made the two countries more reluctant to go to war.

Instead, the USA and the USSR became embroiled in an arms race in which each side tried to ensure that their nuclear weapons were more powerful than those of their rival.

Okay, let's take a moment now to check your understanding.

The statement on the screen says: "The American decision to use atomic bombs against Japan made Stalin change his ideas about how to keep the USSR safe." Is this statement true or false? Pause the video now and press play when you're ready to see the correct answer.

Okay, well done if you said that the statement was false, but we need to be able to justify this response, so on the screen now are two statements.

Statement A says: "It strengthened Stalin's belief that he had to keep the USSR safe by controlling the countries in Eastern Europe.

Statement B says: "It strengthened Stalin's belief that he had to keep the USSR safe by agreeing to free elections in Eastern Europe." Which one of these statements best justifies that our original statement was false? Pause the video now and press play when you're ready to see the correct answer.

Okay, well done if you said it was statement A.

The USA's decision to use atomic bonds against Japan strengthened Stalin's belief that he had to keep the USSR safe by controlling the countries in Eastern Europe.

Okay, let's do another quick check for understanding.

The question on the screen says, "When did the USSR successfully test their first atomic bomb?" Was it A: the 29th of August, 1947, B: the 29th of August, 1948, C: the 29th of August, 1949, or D: the 29th of August, 1950.

Pause the video now, press play when you're ready to see the correct answer.

Okay, well done if you said that the correct answer was C, the 29th of August, 1949, just four years after the Americans.

You are now ready for the second practise task of this lesson, and what I want you to do now is explain two consequences of the USA successfully developing an atomic bomb in July, 1945.

You might wish to consider the following: the response of the USSR and the impact on US-Soviet relations.

Pause the video now and press play when you're ready to compare your answer to a model response.

Okay, very well done for your hard work on that task.

You were asked to explain two consequences of the USA successfully developing an atomic bomb in July, 1945, and your answer may include: "One consequence of the USA successfully developing an atomic bomb was that it led to the USSR developing their own.

Stalin had seen the appalling destruction and loss of life that American atomic bombs had caused in Hiroshima and Nagasaki.

He believed that unless the USSR developed their own atomic bomb, the USA would be able to blackmail and intimidate them.

Therefore, the USSR quickly developed the necessary technology and were able to successfully test their own atomic bomb in August, 1949." Well done if one of your paragraphs is similar to the one that we've just gone through.

Let's take a look at what else you could have written.

Your answer may also have included: "Another consequence of the USA successfully developing an atomic bomb was that it led to significant increase in tension between the USA and the USSR.

Stalin was angry that he had not been informed of the Manhattan Project until the Potsdam Conference, believing that Truman wanted to use this powerful new weapon to intimidate the USSR.

This pushed Stalin to tighten his control over Eastern Europe to show that the USSR could not be intimidated, which only increased tensions even further." Very well done for all your efforts on that task, and particularly if your paragraphs were similar to the model answers that we've just gone through.

We're now ready to move to the final part of our lesson where we're going to be examining the long and Novikov telegrams to understand what they tell us about US-Soviet relations.

The timeline on the screen identifies some of the key events that we're going to be learning about in this final section of our lesson.

In 1946, concerned about escalating tensions due to the breakup of the Grand Alliance, Truman and Stalin asked their embassies to report on attitudes in one another's countries.

As a result, on the 22nd of February, 1946, George Kennan, an experienced diplomat who'd lived and worked in the USSR for a long time, sent a telegram to the US government about the USSR.

Telegrams are normally very short, but Kennan's was long and read like a letter, so it has become known as the Long Telegram.

Kennan's experience meant his views were very well respected by the US government, and the message he sent was alarming.

In the Long Telegram, Kennan expressed his view that the USSR was an aggressive power that wanted to destroy capitalism.

He argued that Soviet expansion and the spread of communism could be prevented if the USA took firm action.

The Long Telegram had a huge influence on Truman's policies towards the USSR and strengthened his determination to stop the spread of communism.

Later that same year, Stalin received a similar telegram from a Soviet official in Washington called Nikolai Novikov.

Novikov's telegram argued that the USA wanted to use their immense military power to dominate the world.

Novikov claimed that the American people were no longer interested in working with the USSR and that they would support their government even if this led to war.

The Novikov Telegram must have confirmed Stalin's worst suspicions about the USA and strengthened his belief that developing control over Eastern Europe was essential if the USSR was to be safe.

Sent in the year after the Second World War ended, the Long and Novikov telegrams provide historians with an insight into the deepening suspicion and hostility that divided the USA and the USSR, former allies who had become enemies in a new conflict.

Let's take a moment now to check your understanding.

What did George Kennan say about the USSR in the Long Telegram? I want you to summarise his message in a short paragraph.

Pause the video now and press play when you're ready to see a model response.

Okay, well done for your hard work on that task.

Your answer may include the following: "In the Long Telegram, Kennan argued that the USSR was an aggressive country and they wanted to destroy capitalism and spread communism.

Kennan said that the USSR could only be stopped if the USA took firm action." Well done if you've got that correct.

Let's do another quick check.

What did Nikolai Novikov say about the USA in the Novikov Telegram? Summarise his message in a short paragraph.

Pause the video now and press play when you're ready to see a model answer.

Okay, well done for your hard work on that question.

The Novikov Telegram warned Stalin that the American people no longer wished to work with the USSR.

It stated that they would support their government against the USSR even if this meant war.

Very well done if you got that correct.

We're gonna do one final check for understanding before we move on to the final practise task of today's lesson.

The paragraph on the screen contains four mistakes and is incorrect.

I want you to identify and correct the mistakes in the paragraph.

Pause the video now and press play when you're ready to see the correct answer.

Okay, well done for your hard work on that task.

You were asked to read the paragraph to identify and correct the mistakes.

The corrected paragraph should read as follows: "The Long Telegram and the Novikov Telegram were sent in 1946 after the USA had used atomic bombs for the first time.

They revealed that the relationship between the USA and the USSR was becoming more hostile.

The Long Telegram made Truman more determined to stop the spread of communism.

The Novikov Telegram strengthened Stalin's belief that the USSR had to take control of Eastern Europe." Well done if you managed to identify and correct all of those mistakes.

We're now ready for the final practise task of this lesson.

I want you to write one paragraph to explain the impact the Long and Novikov telegrams had on the relationship between the USA and the USSR.

Pause the video now and press play when you're ready to see a model response.

Okay, well done for all of your hard work on that final practise task.

You were asked to write one paragraph to explain the impact the Long and Novikov telegrams had on the relationship between the USA and the USSR.

Your answer may have included: "The Long and Novikov telegrams increased tension between the USA and the USSR and led to a decline in their relationship.

The Long Telegram warned that Stalin wanted to destroy capitalism and spread communism around the world.

Kennan warned that Stalin could only be stopped if the US took firm action.

This made Truman more determined to take strong action against the USSR.

The Novikov Telegram warned Stalin that the USA no longer wished to work with the USSR and that they may even be prepared to go to war.

This led to an increase in tension because it made Stalin more determined to take control of Eastern Europe to help ensure the USSR was safe from invasion.

Fantastic effort on that final practise task, and well done if your response was similar to the one that we've just gone through.

We're at the end of our lesson now, so it's a really good opportunity for us just to summarise some key learning points.

The USA had developed the world's first atomic bomb by July, 1945.

The USA did not inform the USSR of the Manhattan Project, so Stalin found out as much as he could through espionage.

Truman argued that the USA used atomic bombs to force Japan to surrender, but some historians argued that the main purpose was to demonstrate American power, especially to the USSR.

The USSR had developed their own atomic bomb by August, 1949.

The development of the atomic bomb by the USA led to significant increase in tension between the USA and the USSR, which was revealed in the Long Telegram and the Novikov Telegram.

It's been a real pleasure teaching you today.

I hope you've enjoyed the lesson and I look forward to teaching you again soon.