How effectively did the USA contain communism?

Cambridge IGCSE History 0470 · Paper 1 Section A, Core Content Option B Syllabus: 2027 and 2028 Option B: The twentieth century: international relations since 1919 Key Question 5 of six

This file covers one Key Question: whether American containment worked, tested through three case studies that Cambridge names and limits, Korea 1950 to 1953, Cuba 1959 to 1962, and Vietnam 1955 to 1975. If you came here looking for how the Cold War started, for Yalta and Potsdam, for the Berlin Blockade or the Truman Doctrine, you are in Key Question 4, Who was to blame for the Cold War?. If you came looking for Hungary 1956, Czechoslovakia 1968, the Berlin Wall, Solidarity or Gorbachev, you are in Key Question 6, How secure was the USSR's control over Eastern Europe, 1948 to c.1989?. Section 2 draws those lines exactly, because these three Key Questions overlap more than any other trio in the course.

The command word that governs everything below is effectively. Not "what happened in Korea". Not "why America went into Vietnam". How well it worked. That means every case study in this file is set out twice, once as evidence that containment succeeded and once as evidence that it failed, because a 10 mark answer that only runs one of those two cases is capped in the middle of the mark range no matter how much detail it carries.

1. What the syllabus actually asks

This is the wording printed in the Cambridge IGCSE History 0470 syllabus for 2027 and 2028. Learn the Key Question itself: examiners build 10 mark questions directly out of it, and one paper in this corpus simply reprinted it as the question.

Key Question 5

How effectively did the United States contain the spread of communism?

Focus points

The syllabus introduces them with a sentence it uses nowhere else in Option B:

This key question will be explored through case studies of the following:

• The United States and events in Korea, 1950 to 1953
• The United States and events in Cuba, 1959 to 1962
• American involvement in Vietnam, 1955 to 1975

Specified content

Case studies of:

• American reactions to North Korea's invasion of South Korea, the involvement of the UN, the course of the war to 1953
• American reactions to the Cuban Revolution, including the Missile Crisis and its aftermath
• American involvement in the Vietnam War, including reasons for involvement, tactics and strategy, reasons for withdrawal

Cambridge prints the three date ranges in shortened form, as 1950 to 53, 1959 to 62 and 1955 to 75, joined by a dash rather than by the word. These notes write them out in full. Nothing else about the wording has been changed.

The one focus point structure that is different from every other Key Question

In the other five Key Questions of Option B, the focus points are questions: "Why did the victors not get everything they wanted?", "Was the policy of appeasement justified?", "Why was the Berlin Wall built in 1961?". Each one is effectively a ready made essay title.

Key Question 5 is the exception. Its focus points are not questions at all. They are three case studies and a date range each, and the specified content underneath them is the same three case studies broken into sub headings. Cambridge has replaced the arguments with a scope boundary.

That has one useful consequence and one dangerous one.

The useful consequence. The scope is unusually tight and unusually clear. Three theatres, three date ranges, three named strands each. Nothing else is specified content in this Key Question.

The dangerous one. Because Cambridge has not written the arguments for you here, it is very easy to revise this Key Question as three narratives and then be unable to answer the question that is actually set. Every 10 mark question in this corpus asks about success, failure, importance, surprise or comparison. None of them asks you to tell the story. Sections 4, 5 and 6 below therefore supply the argument structure that the syllabus leaves out.

A note on the syllabus wording

The syllabus prints the option title two ways. The contents page and the subject content introduction both call it The twentieth century: international relations since 1919, while the header on the Option B content page reads from 1919. They mean the same thing. Use "since 1919".

2. Where this Key Question stops, and where 4 and 6 begin

These three Key Questions share a decade, a pair of superpowers and a vocabulary. Cambridge draws the lines by place, not by theme.

Two boundaries repay a second look, because the mark schemes handle them in ways the table does not fully predict.

The Truman Doctrine and Marshall Aid sit in Key Question 4, but they are creditable here. The whole containment 10 mark question set in November 2021 lists at Level 2, among the acceptable points, "The Marshall Plan prevented some states becoming communist in Europe" and "The Berlin Airlift saved West Berlin from becoming communist". So when the question is about containment as a whole policy, European examples earn marks. When the question names Korea, Cuba or Vietnam, they do not. Read the question stem, not the topic.

Containment itself gets set as a 4 mark question in both Key Questions. "What was the policy of containment?" appears as question 7(a) in November 2022 and again as 7(a) in June 2024, and on both occasions the rest of question 7 was Key Question 4 material, the Greek Civil War and the Berlin Blockade. The definition is shared property. What follows it in parts (b) and (c) tells you which Key Question you are actually in.

Going the wrong way costs marks in both directions. The November 2018 examiner report notes that on a question about the beginning of the Cold War, "A number of responses were focused primarily upon events in Vietnam and the Cuban Missile Crisis; these were not relevant to a question asking about the beginning of the Cold War."

3. How Paper 1 sets this Key Question

The generic marking is not repeated here. The paper structure, the assessment objective weights, the 4 / 6 / 10 split, all three level ladders, the two rules Cambridge changed for the 2024 series and the faults examiners name on every question are set out in the How Cambridge marks History 0470 Paper 1 notes. Read that page first. What follows is only what is true of this Key Question and not of the others.

It is set in half of all papers, and it is usually question 7

Forty eight Paper 1 mark schemes from the 2018 to 2024 series were read for these notes. Twenty four of them set a question on Key Question 5. That is exactly half, and it is a higher hit rate than any student should expect from a Key Question that occupies a single page of the syllabus.

It never appeared as question 5 or question 6 in any paper read. Those two slots go to Key Questions 1 to 3, the Treaty of Versailles, the League and Hitler's foreign policy. This matches the syllabus rule that in each option two Section A questions come from Key Questions 1 to 3 and two from Key Questions 4 to 6.

From the 2024 series onward that rule bites harder than it used to. Papers up to 2023 carried a fourth Option B key question on Iran and Iraq, so questions 7 and 8 had three Key Questions to share between them. That question disappeared from the 2024 series, and in the six 2024 papers read, questions 7 and 8 divide cleanly between Key Questions 4, 5 and 6. Two slots, three Key Questions. One of the three is left out of every paper, and in the 2027 and 2028 syllabus it will still be two slots and three Key Questions. Revising only Korea, or only Vietnam, is a bet that the one case study you know is the one that gets picked.

The case studies come up in near equal proportion, and questions mix them

Across the 72 sub parts in those 24 questions, counting a comparison question on both sides:

Vietnam is marginally the most examined and Korea the least, but the gap is small enough to be noise. There is no case study you can safely skip.

The more useful pattern is inside the questions. Half of the 24 questions used more than one case study within the same question. June 2022 set MacArthur in Korea at (a), the Bay of Pigs at (b) and Vietnam at (c). March 2021 set Korea, then Cuba, then Vietnam, in that order, in one question. June 2022 v3 set Cuba, then Vietnam, then Korea. A candidate who knows one case study very well and the others barely can be stopped at part (b) of a question they thought was theirs.

The other half of the questions ran one case study through all three parts. Both shapes are live.

It is not a Paper 2 prescribed topic in 2027 or 2028

Paper 2 sets its sources on a single prescribed topic that changes each series. The syllabus prints the list for both years covered by this specification. For Option B they are:

• 2027: Was the Treaty of Versailles fair? (March, India only), How secure was the USSR's control over Eastern Europe, 1948 to c.1989? (June), Was the Treaty of Versailles fair? (November)
• 2028: Who was to blame for the Cold War? (March, India only), How far was Hitler's foreign policy to blame for the outbreak of war in Europe in 1939? (June), Who was to blame for the Cold War? (November)

Key Question 5 is not on either list. In these two years it is a Paper 1 topic only. That is worth knowing when you plan revision time: this is a Key Question that pays on one paper, and it pays on that paper about half the time.

4. What containment was, and what "effectively" is being measured against

Before the case studies, get the yardstick right, because "how effectively" needs something to be effective at.

Cambridge's own 4 mark schemes define containment tightly, and the definition is narrower than most students assume. From the November 2022 and June 2024 mark schemes for "What was the policy of containment?":

• Containment was a policy to stop the spread of communism
• It was to halt the spread of Soviet influence
• It was designed by Truman
• It did not aim to roll back Soviet influence in states already under communist control

That last line is the one that does the work. Containment is not liberation. The test of containment is not whether communism was destroyed anywhere. It is whether it got any further.

1. containment aims to stop the spread, not to reverse it
2. so a country that was already communist staying communist is not a failure of containment
3. and a country that was not communist becoming communist is
4. this is why Cuba and Vietnam are argued so differently

The second yardstick is the domino theory, which appears in mark schemes for all three case studies. Cambridge's own phrasing, from several schemes: if one country fell to communism then the surrounding ones would follow. In Korea the named dominoes are Formosa and Japan. In Vietnam they are Laos, Cambodia and Thailand. The domino theory is what turns a local war into a test of containment, and it is also the thing you can measure the outcome against: did the dominoes fall or not?

1. the United States judges each crisis by whether communism spreads beyond it
2. so the mark of success is the border staying where it was
3. and the mark of failure is neighbouring states following
4. Korea and Vietnam are therefore assessed by exactly the same test and produce opposite answers

A warning about the word. The March 2018 mark scheme includes, at Level 2 on a question about containment between 1950 and 1975, the point "President Nixon ended the containment policy". That is Cambridge crediting the idea that containment as a policy has an end date inside the period. If a question gives you dates, respect them, and do not assume the policy ran unchanged across the whole quarter century.

5. Case study one: the United States and events in Korea, 1950 to 1953

The syllabus splits this into three strands: American reactions to the invasion, the involvement of the UN, and the course of the war to 1953. All three appear as separate question stems in the corpus, so treat them separately.

American reactions to North Korea's invasion

North Korean forces crossed the 38th Parallel on 25 June 1950, after a series of border clashes. The North claimed the South had attacked first.

Why the United States treated a border war in Asia as a superpower crisis is the single most examined thing about Korea in this corpus. It has been set as "Why was the USA concerned about North Korea's invasion of South Korea?" (March 2018) and as "What was Truman's attitude to the North's invasion of South Korea?" (November 2023). Cambridge's own accepted answers:

• Truman blamed the Soviet Union for the attack. The mark schemes phrase it as: the actions of North Korea were seen as part of Moscow's attempt to gain world domination.
• Truman feared the spread of communism into Asia, and specifically that if South Korea fell, Formosa and Japan could be next.
• The USA had a policy of containment and this was the first military test of it. The March 2018 scheme includes "The USA decided a firm response to the first communist threat would be effective."
• The USA had helped establish the Republic of Korea and thought of itself as South Korea's protector.
• Truman mobilised the US navy around the Korean coast and appealed to the United Nations.

1. Truman reads a local invasion as a Soviet probe
2. a Soviet probe unanswered invites more probes
3. Formosa and Japan are the next dominoes
4. so a firm response in Korea is not about Korea, it is about the credibility of containment everywhere

Note what is not in the American reaction according to Cambridge: nothing about defending democracy in the abstract, and nothing about Korean self determination. Syngman Rhee, the South Korean leader, appears in the mark schemes only as the man the UN failed to unite Korea under.

Why North Korea invaded, which is a different question

Set as 7(b) in November 2023. Cambridge's accepted reasons, in its own terms:

• Kim Il-Sung wanted to unite Korea under communist rule and saw North Korea as the legitimate government of Korea
• He had the backing of communist leaders such as Stalin
• North Korean forces were stronger than those of South Korea
• He thought the US would not get involved

That last point matters for the effectiveness argument. If containment had been visibly credible in Asia in 1950, the invasion might not have happened at all. Cambridge credits the idea that the United States had not made its commitment clear.

The involvement of the UN

This is a named strand of the specified content and it was set as its own 4 mark question in March 2018, "What happened at the United Nations Security Council meetings in June and July 1950?". The chain the mark scheme accepts:

• The Security Council met the day the North Koreans invaded
• It passed a resolution demanding that hostilities cease and that North Korean forces withdraw to the 38th parallel
• The resolution passed because of the absence of the Soviet representative, who, it was thought, would have used his veto
• When North Korea refused to obey, a second resolution called on UN members to provide troops
• A third resolution placed those forces under a unified command held by the USA
• The UN forces were placed under the command of General MacArthur

1. the Soviet delegate is absent from the Security Council
2. the veto that would have blocked action is not cast
3. the UN can authorise force against a communist state
4. the United States gets to fight a containment war under an international flag
5. and the UN gets tied to an American commander and an American war aim

Cambridge's schemes say sixteen countries sent troops. The proportion of them who were American is disputed inside Cambridge's own documents, and section 11 sets out that conflict rather than picking a side.

The course of the war to 1953

The sequence Cambridge credits, drawn from the June 2020, November 2019, June 2022, March 2021 and November 2024 mark schemes:

The MacArthur dismissal is the most instructive single episode for the effectiveness question, and it has been set twice, in June 2020 and again in November 2024. Cambridge's model explanation: Truman was content to save South Korea, MacArthur wanted to continue the war, invade China and use nuclear weapons, and Truman was worried that attacking China was too dangerous and might bring the Soviet Union into the war. One accepted Level 2 point puts it exactly: "Truman wanted to follow a policy of containment and nothing more."

1. MacArthur wants to destroy communism in Asia
2. Truman wants only to stop it spreading
3. the two aims are incompatible once UN troops cross into North Korea
4. Truman sacks his own commander to keep the war limited
5. containment is confirmed as a policy with a deliberate ceiling, not a failure to win

Cambridge also credits the Chinese intervention as decisive. The November 2019 scheme explains that UN commanders underestimated how skilful and numerous the Chinese troops were, mistook a tactical withdrawal in October 1950 for a retreat, and were then driven out of North Korea entirely.

The case that containment worked in Korea

• South Korea survived and stayed non communist. This is the core point and Cambridge's schemes state it flatly: the USA had stopped the spread of communism in South Korea.
• The dominoes did not fall. The June 2018 examiner report praises answers that explained that "the domino effect, which the Americans feared, did not happen, therefore pressure was taken off Formosa and Japan."
• The war was fought and finished within its limits. The border ended where it started. Truman's stated aim was achieved and MacArthur's wider war was refused.
• Collective security worked where the League of Nations had failed. Cambridge's March 2019 scheme argues explicitly that Korea "shows that it was stronger than the League of Nations and could act with force even when major countries such as China were involved."

The case that it did not

• Korea was not unified or made democratic, which was the declared UN aim once forces crossed the parallel. Several schemes credit "The UN failed to achieve a unified and democratic Korea."
• North Korea survived as a communist state and gained powerful allies. The November 2024 model Level 5 answer argues, in Cambridge's own words, that "probably North Korea was the more successful", because it had pushed the US back to the 38th parallel, gained vital support from China and the Soviet Union, and remained communist.
• The war ended where it began. An armistice, not a peace. South Korea refused to sign it.
• The UN's independence was compromised. Accepted points include "The UN was seen as a creature of the USA" and "It was a US effort to contain communism and had little to do with the UN."
• Casualties were high. Cambridge's schemes say so, in those words, and do not print a number. Do not supply one.

Judgement material for Korea

The question Cambridge sets most often on Korea is not whether the war was won but whose success it was: the UN's, the USA's or North Korea's. Note the trap in that: a candidate primed to argue about containment can find themselves answering a question that is really about the United Nations. The November 2023 examiner report puts it precisely, that "few responses could present a case about the United Nations in combatting communism, rather than being an organisation to secure and maintain peace." The UN was founded to keep the peace. Judged as a peacekeeper it did well. Judged as an instrument of American containment it did well too, and those are two different verdicts on the same events.

6. Case study two: the United States and events in Cuba, 1959 to 1962

The specified content names two things and adds a third by implication: American reactions to the Cuban Revolution, the Missile Crisis, and its aftermath. That last word extends the case study past the 1962 boundary in the focus point, and Cambridge uses the extension: mark schemes credit Khrushchev's fall from power in 1964 and the setting up of the hotline.

American reactions to the Cuban Revolution

Castro overthrew the Batista regime in 1959. Cambridge's 4 mark scheme for "Who was Fidel Castro?" credits: he was a lawyer, he campaigned against Batista, he promised the Cuban people their land, he reorganised healthcare and offered free education, he arrested and exiled political opponents, he took over US businesses in Cuba, he received arms from the USSR, and he allowed the US to keep a naval base on Cuba.

Eisenhower's reaction, set as a 4 mark question in June 2022:

• He imposed economic sanctions, refusing to buy Cuban products such as sugar
• He announced the USA would not buy oil from Cuba
• He was concerned that Castro was getting closer to the USSR
• He agreed to support an invasion of Cuba by Cuban exiles and planned to replace Castro with an exile

In 1960 Castro declared himself a communist and an ally of the USSR.

1. the United States applies economic pressure to a revolution on its doorstep
2. the pressure pushes Castro toward the only other buyer for Cuban sugar
3. Cuba signs trade agreements with the USSR and receives Soviet arms
4. the containment measure helps produce the alignment it was meant to prevent

That chain is worth having ready. It is the strongest single argument that containment in Cuba was self defeating, and it is built entirely from points Cambridge itself credits.

The Bay of Pigs, 1961

Set repeatedly: as 7(a) in June 2020, 8(a) in March 2024, 7(b) in June 2021, 8(b) in June 2022, and 8(b) in June 2023. It is the most set single episode in the Cuban case study.

What Cambridge credits:

• The plan was put together under Eisenhower; Kennedy, newly president, decided to go ahead with it
• Kennedy supplied anti-Castro exiles with arms, equipment and transport; they were funded and trained by the CIA
• The exiles landed at the Bay of Pigs; American bombers attacked Cuban airfields
• Kennedy decided against sending more air support
• Within days all the exiles were captured or killed

The June 2023 examiner report and the March 2024 examiner report both quote figures: 1400 anti-Castro exiles, met by 20,000 Cuban troops armed with tanks and modern weapons. The November 2024 mark scheme repeats the 1400 figure. Those are Cambridge's own numbers and are safe to use.

Why it mattered, which is what the 6 mark questions ask:

• It humiliated Kennedy, a new and inexperienced president, and made him look weak
• It made Castro stronger in Cuba and strengthened the revolution
• It pushed Cuba closer to the Soviet Union
• It made Khrushchev think he could bully and outmanoeuvre Kennedy, which is why he thought he could get away with putting missiles in Cuba
• It meant Kennedy was determined not to be humiliated by Cuba again
• Kennedy ordered a trade embargo against Cuba
• It highlighted the failure of the CIA

The Missile Crisis, October 1962

Kennedy's handling has been set as a 4 mark question at least twice. Cambridge credits:

• He met for thirteen days with advisers, deciding how to react
• He imposed a blockade, publicly called a quarantine
• He made a speech to the US public explaining his plan
• He got troops ready for an invasion; all US forces worldwide were placed on DEFCON 3
• Soviet ships were turned back by the blockade
• He agreed to lift the blockade and not to invade Cuba if the missiles were removed
• He secretly agreed to remove US missiles from Turkey
• He agreed to set up a direct hot-line phone link

Two further details Cambridge credits and candidates often miss: Kennedy ignored Khrushchev's second letter and responded to the first, and he ignored the shooting down of a US U2 spy plane rather than treat it as grounds for war.

Why the missiles were a problem, from the 6 mark schemes: Cuba was communist, anti-American, and only 90 miles from the USA; the missiles could reach most of the continental United States; the presence of the missiles would change the balance of power; and it was difficult to see how the US could remove them without causing a war.

Why Khrushchev placed them, which is the other side of the same crisis and has its own 6 mark question: to defend Cuba from an American invasion the Bay of Pigs had made look likely; to close the missile gap, since he could not threaten the US from Soviet soil but could from 90 miles away; and to strengthen his own position at home, because members of the Soviet government thought he was not aggressive enough toward the United States.

The case that containment worked in Cuba

• The missiles were removed. The immediate threat was ended without war.
• Kennedy's reputation was made. He stood up to hardliners in his own government who wanted him to invade, and he stood up to Khrushchev. The American press praised him and he became more popular.
• The blockade forced Khrushchev to negotiate, and Khrushchev backed down.
• Khrushchev lost. He was forced from power in 1964, and the removal of American missiles from Turkey, one of his gains, was secret, so he could not use it for propaganda.
• Communism was contained in Cuba for the immediate future. The mark schemes use exactly that phrase.

The case that it did not

• Cuba stayed communist. Castro remained in power, allied to the USSR. Accepted points include "The USA had a communist country within its sphere of influence" and "Communists were attracted to Cuba to plan ventures into Central and South America."
• The United States promised not to invade. Containment in Cuba was purchased by a permanent guarantee to a communist state 90 miles offshore.
• The USA had to remove its missiles from Turkey, a concession, even if a hidden one.
• Khrushchev achieved his main aim. Cambridge's own model answer states it: "the crisis did achieve Khrushchev's aim of defending Cuba and keeping it safe."
• Kennedy's critics were not satisfied. Several schemes credit "Some of Kennedy's critics did not want to see communism on the US' doorstep."
• The Bay of Pigs had already failed on the same objective a year earlier.

The word to be careful with

Note that "Cuba stayed communist" is a strong point against American policy but a weaker point against containment as defined, because containment did not aim to roll back communism where it already existed. That distinction, taken from Cambridge's own definition in section 4, is exactly the kind of sentence that turns a Level 4 answer into a Level 5 one. It is a judgement, not a fact.

7. Case study three: American involvement in Vietnam, 1955 to 1975

The specified content names three strands and they map straight onto three arguments: reasons for involvement, tactics and strategy, and reasons for withdrawal. Structure your revision that way, because Cambridge structures its questions that way.

One date warning. The focus point begins in 1955, but the mark schemes routinely credit 1954 material, the French defeat at Dien Bien Phu and the division of Vietnam into North and South. Cambridge's own March 2019 scheme lists both. Use them as background to reasons for involvement, and do not build an answer out of the French war.

Reasons for involvement

• The French were defeated and left in 1954; Ho Chi Minh defeated them at Dien Bien Phu; Vietnam was divided and the North became communist
• The domino theory: if Vietnam fell, the Americans feared Laos, Cambodia and eventually the whole of South East Asia would follow
• The communist Vietcong worked to overthrow Diem in the South, and the domino theory meant the USA could not let Diem's regime fall
• The Vietcong and North Vietnam were being helped by China and the Soviet Union
• In 1959 North Vietnam increased its military assistance to the Vietcong

Kennedy's involvement, set as its own 4 mark question in June 2020: he said he would support the government of South Vietnam against the communist threat; he supported the domino theory; the Strategic Hamlet programme was introduced during his presidency; he financed an increase in the size of the South Vietnamese army; in 1961 he began increasing the number of US advisers; by 1962 there were 11,000 military advisers in South Vietnam; he tried to persuade Diem to introduce reforms; and he was planning to withdraw US advisers by the end of 1963.

Johnson's escalation, set at least twice as a 6 mark question. The mechanism Cambridge credits:

• In August 1964, American warships in the Gulf of Tonkin were attacked by North Vietnamese gunboats
• Congress passed the Gulf of Tonkin Resolution, giving Johnson authority to take whatever action he thought necessary
• Johnson ordered strikes against North Vietnam, and ground troops were sent in 1965

Cambridge also credits less flattering motives at Level 2: there was an election looming and Johnson did not want to be the first US President to lose a war, and Johnson had asked his generals to prepare war plans before Tonkin.

1. a naval incident gives Congress a reason to hand the President open authority
2. the President uses it to bomb the North and then to commit ground troops
3. an advisory commitment becomes a war without any single decision to go to war
4. which is why "reasons for involvement" is a chain question, not a list question

Tactics and strategy

This is a named strand and it is examined from both sides.

Vietcong tactics, set as a 4 mark question in June 2021: guerrilla warfare; winning the support of the peasants, who fed and hid them; hiding in villages and pretending to be peasants; booby traps and ambushes; retreating when the Americans attacked so no conventional battle could be fought; networks of tunnels for escape and surprise attacks; working in small cells; no uniforms; hit and run raids; the Ho Chi Minh Trail for supplies; no known base.

American tactics, and the problems each created:

1. American firepower is designed to destroy an enemy that concentrates
2. the Vietcong refuse to concentrate and hide among civilians
3. so American firepower falls on villages
4. the villages support the Vietcong more
5. and the pictures come home on television

The Tet Offensive, January 1968

Set as a 4 mark question in June 2021, a 6 mark question in June 2021 and again in November 2024, and it appears inside 10 mark answers constantly. It is the single most examined episode in the Vietnam case study.

What Cambridge credits: North Vietnamese troops and Vietcong attacked South Vietnamese towns and cities, government buildings and US bases in over 120 attacks; Vietcong fighters got inside the US Embassy in Saigon; the attacking forces were spread thinly and US and South Vietnamese troops counter attacked; the communists took Hue and executed many people connected with the Americans, and Hue was retaken; the attacks were stopped, but they had shown the war was not nearly over; Johnson halted escalation and called for peace talks; opposition to the war in the US increased.

The point that earns marks is the paradox, and Cambridge states it in its own model answer: Tet was a military defeat for North Vietnam and a political defeat for the United States. The Americans had been told the North was weak and incapable of launching large attacks. Tet showed that was wrong, and the US government could not persuade the American people otherwise.

Reasons for withdrawal

This strand splits neatly into two sides, which is why so many 10 mark questions are built on it.

Events in Vietnam:

• The Vietcong could not be defeated by conventional means; they had local support, local knowledge and no fixed base
• The regime in South Vietnam was corrupt and unpopular, and arguably not worth defending
• North Vietnamese forces were supplied by China and the Soviet Union and were fighting to unite their own country
• Tet showed the war was unwinnable

Events in the United States:

• Television. This was the first televised war. Americans saw napalm, burned children and massacred villagers.
• My Lai. Cambridge's November 2022 model answer describes 300 villagers, mainly women and children, killed by US troops; the November 2024 scheme says "hundreds of unarmed Vietnamese civilians". Cambridge's own documents differ on the figure, so if you use one, use it as approximate.
• Cost. Cambridge's schemes say America was spending between $20 and $30 billion a year, and quote Life Magazine calculating in 1967 that it cost $400,000 for each Vietcong guerrilla killed. Spending on social reform was cut to pay for the war.
• Casualties and the draft. Cambridge credits nearly 500,000 troops in Vietnam at peak and, in a separate scheme, over 2 million US troops deployed across the war. The draft, also called Selective Service, took 2.2 million American men; 25 per cent of the force in combat zones were draftees; most were from poor and working class families; thousands fled to Canada and some used college to avoid it.
• Protest. In 1969, 250,000 people demonstrated in Washington; in 1970 the National Guard shot dead four student protestors. Cambridge's schemes also name Walter Cronkite's reports for CBS, and the examiner report for March 2024 names the protests at Kent University.
• Johnson decided not to stand for re-election.

Nixon and Vietnamisation. Nixon's policy was to encourage the South Vietnamese to fight alone, with American weapons and money but without American troops, in pursuit of what he called "peace with honour". Between December 1970 and September 1972 over 300,000 US troops were removed. When peace talks failed, Nixon bombed North Vietnam and Cambodia, which caused public outrage at home.

The Paris Peace Accords, 1973, set as a 4 mark question in June 2023 and answered badly. They ended the Vietnam War and were intended to establish peace; they were signed by North Vietnam, South Vietnam and the USA, with Henry Kissinger signing for the USA under President Nixon; US troops had to leave and advisers withdraw within 60 days; prisoners would be returned; a ceasefire was established in South Vietnam; there would be free elections in the South; and Vietnam would be unified by peaceful means.

Fighting broke out again. South Vietnamese forces were no match for the North Vietnamese army and the South was captured in 1975.

The case that containment worked in Vietnam

This is the harder side and the one candidates skip, which is exactly why it is worth having. Cambridge credits:

• The motive was sound even if the outcome was not. Its own model answer runs: "I do not think it was an error. This is because of the domino theory... China and North Korea had fallen and it looked as if Vietnam would be next."
• Vietnamisation could have worked. Cambridge's model answer argues that by 1971 it "had achieved some rollback of Communist gains inside South Vietnam", and that the South was abandoned when the promised American support was not sent in 1974, not because the policy was unworkable.
• Tet was a military defeat for the communists, which showed they could be beaten.
• The war delayed communist victory by two decades and absorbed communist resources.

The case that it did not

• The whole of Vietnam became communist. This is the plainest failure of containment anywhere in the Key Question.
• The dominoes fell. Cambridge's schemes state repeatedly that Laos and Cambodia also became communist as a result.
• The Americans lost domestic consent, which is a failure of the policy and not only of the war.
• The cost was enormous and delivered nothing.
• The United States could not win a guerrilla war with conventional forces, and never adapted.

8. Putting the three together

Two of the 24 questions asked about containment as a single policy rather than one case study: "How far was the US policy of containment between 1950 and 1975 a failure?" (March 2018) and "How far do you agree that the US failed to contain the spread of communism?" (November 2021). Three more asked for a direct comparison between two case studies. This section is for those.

The shape Cambridge rewards

The June 2018 examiner report is unusually explicit about structure, and it is the only place in this corpus where examiners tell you how to organise a comparison:

A number of candidates attempted to compare both conflicts throughout their answer which often affected the structure of the essay and became more of a list and led to confusion. Stronger responses dealt with the USA's approach to containment with each situation separately and then made a comparative conclusion.

One case study, then the other, then the comparison. Not a running back and forth.

The three case studies as a single argument

1. containment succeeds in Korea and holds in Cuba and collapses in Vietnam
2. the three outcomes are not equally weighted, because Vietnam ran for twenty years and cost more than the other two combined
3. so a chronological answer that ends in 1975 reads as failure, while an answer weighted by objectives achieved reads as two out of three
4. which of those weightings you choose is your judgement, and stating it is the tenth mark

The trap in the whole containment question

Cambridge's Level 1 example for the November 2021 whole containment question is: "The policy of containment was designed to stop the spread of communism." That is a correct sentence and it earns one mark out of ten, because it does not address the question. Defining containment is not answering a question about how well it worked.

The November 2021 examiner report ends with the sentence that governs this whole Key Question: "It is important to link points made to the question."

9. What the papers actually ask

The 4 mark families

Four separate points, no credit for elaboration from the 2024 series onward. The families that recur:

• Describe an episode: the Bay of Pigs, the Tet Offensive, the Korean invasion of June to September 1950, the Cuban Revolution, how the fighting in Korea ended in 1953, the UN Security Council meetings of June and July 1950
• Define a term: containment, the quarantine, Operation Rolling Thunder, the Vietcong, the draft, the Gulf of Tonkin incident, the Paris Peace Accords
• Identify a person: Fidel Castro, MacArthur's role in the Korean War
• State an attitude or a reaction: Truman's attitude to the invasion of South Korea, the USA's attitude to the communist invasion, Eisenhower's reaction to the Cuban revolution, Kennedy's actions in relation to Vietnam or in the Missile Crisis

The 6 mark families

Two explained reasons for 6. The recurring stems:

• Why the USA was concerned about the invasion of South Korea; why North Korea invaded; why Chinese support for North Korea was important; why MacArthur was dismissed
• Why Kennedy went ahead with the Bay of Pigs; why he was humiliated by it; why the Bay of Pigs was important; why he imposed the blockade; why Khrushchev placed missiles in Cuba; why the missiles were a problem for the USA; why the crisis was resolved peacefully
• Why developments in Vietnam in the 1950s mattered to the USA; why Johnson escalated; why search and destroy created problems; why the Vietcong could withstand US attacks; why the Tet Offensive was important, or disastrous for the USA; why US public opinion turned against the war; why containment failed in Vietnam

The 10 mark families

One explanation on each side is 7. A stated judgement is the tenth mark. The families:

10. Judgement sentences for this question

Level 5 is Level 4 plus a stated position with a reason attached. These are shaped for this content specifically. Adapt, do not copy.

• "Containment worked where the United States kept its aims limited, and failed where it did not, which is why Korea ended in an armistice and Vietnam ended in a defeat."
• "Judged by its own definition, stopping the spread rather than reversing it, containment succeeded in two of the three case studies, and the one where it failed is the one that shaped how the policy is remembered."
• "Cuba was a success for the crisis and a failure for the policy, because the missiles left and the regime stayed."
• "The Korean War was a victory for containment and only an ambiguous one for the United Nations, because the UN's stated aim of a unified and democratic Korea was the aim that was abandoned."
• "The United States lost in Vietnam because it never found a military answer to a political problem, and its tactics made the political problem worse each time they were used."
• "Khrushchev achieved the aim he cared most about and lost the one he could show his own government, which is why the crisis looks like a defeat in Moscow and a compromise everywhere else."
• "Containment was more effective at holding lines than at winning arguments, and Vietnam was lost in the United States before it was lost in Vietnam."

11. What examiner reports say candidates get wrong here

The general faults, overwriting part (a), listing instead of explaining, one sided 10 mark answers, are in the How Cambridge marks History 0470 Paper 1 notes. These are the ones examiners name on this content.

• Confusing the Tet Offensive with My Lai. Named directly in the June 2021 report: answers "confused the Tet Offensive with other events during the Vietnam War, such as the incident at My Lai". Section 12 flags a complication with this.
• Thinking the Bay of Pigs was part of the Vietnam War. Also June 2021. It sounds absurd until you are in an exam hall.
• Muddling the Cuban chronology. The June 2023 report says candidates "thought the Bay of Pigs was after the American spy plane had flown over Cuba and spotted the missile sites". The order is revolution 1959, Bay of Pigs 1961, missiles 1962.
• Thinking the Bay of Pigs caused Castro to request the missiles. Flagged as an error in June 2021. Cambridge's schemes credit the Bay of Pigs as a reason Khrushchev thought he could get away with it, and as a reason Khrushchev wanted to defend Cuba, not as a Cuban request.
• Not knowing the dates of a president's term. The clearest topic specific trap in the corpus. On "How successful were Nixon's policies in Vietnam?", the March 2024 report says many responses "appeared not to know the dates of Nixon's presidency and wrote at length about policy and events in Vietnam prior to Nixon becoming President, including Search and Destroy, the My Lai massacre and the Tet offensive." All three of those are Johnson era. Nixon owns Vietnamisation, the bombing of Cambodia, the 1973 Accords and Kent State.
• Answering about the war when the question is about the decision to enter it. June 2021, on "US involvement in Vietnam was an error from the beginning": weaker answers "were based around the difficulties the US faced fighting against the Viet Cong during the Vietnam War, rather than focussing on the motivations for involvement from the beginning."
• Writing background instead of argument on Cuba. June 2021 again: "Weaker responses included much narrative on the background to the Cuban Missile Crisis, including the overthrow of Batista and the Bay of Pigs failure for the USA, which were not relevant to this question."
• Knowing Cuba much better than Korea. June 2021 states it plainly: "candidates tended to be more familiar with events in Cuba than with those in Korea". On a comparison question that produces a one sided answer and a capped mark.
• Comparing throughout instead of concluding. June 2018, quoted in full in section 8.
• Not knowing the Paris Peace Accords at all. June 2023: "Candidates struggled with this question or, in some case, left it blank... A common misconception was that it was between the USA and USSR, regarding the reduction of nuclear weapons." Four marks were available for one of the most straightforward 4 mark questions in the corpus.
• Describing without assessing. Named in almost every report on this Key Question, and the November 2021 report gives the fix in one sentence: "It is important to link points made to the question."
• Missing what the question is actually about. The November 2023 report on "The Korean War was a victory for the United Nations": "Few responses could present a case about the United Nations in combatting communism, rather than being an organisation to secure and maintain peace."

12. Where Cambridge's own materials disagree

Three genuine conflicts inside the published documents. Do not try to reconcile them. Know that they exist, avoid staking an answer on the disputed figure, and use the safe version.

The American share of UN forces in Korea. The November 2023 mark scheme prints, inside a credited model answer, "The Korean War was a victory for the USA as it provided 90% of UN forces." The June 2020 scheme prints "90% of the troops sent to help South Korea were American" and, separately, "The US provided nearly all the troops." But the November 2019 examiner report describes strong answers as saying the Americans "had provided half of the ground forces and most of the air and naval forces." Half and ninety per cent are not the same claim. The safe version is qualitative: the United Nations force was overwhelmingly American, commanded by an American, and sixteen countries contributed troops. Cambridge credits all three of those without dispute.

Tet and My Lai. The June 2021 examiner report faults candidates for confusing the Tet Offensive with My Lai. But the November 2024 mark scheme, on "Why was the impact of the Tet offensive disastrous for the United States?", offers as its model Level 3 explanation an answer built entirely on My Lai, describing it as retaliation for the attacks on US bases, and lists at Level 2 "The reaction of some US troops to the Offensive led to the massacre at My Lai." So Cambridge has moved from treating the connection as an error to crediting it as an explanation. The safe version: treat them as two separate events with a causal link Cambridge now accepts, and never write as though they were the same event.

Who attacked at Tet. The June 2021 report lists among the errors candidates who "thought that it was an attack by the North Vietnamese", while both the June 2021 and November 2024 mark schemes credit North Vietnamese troops alongside the Vietcong. The safe version: both, which is what the schemes say.

One more thing to be careful about, which is not a conflict but a gap. Cambridge's mark schemes and examiner reports for this Key Question refer repeatedly to high casualties in Korea and Vietnam and never print a total. "The Korean War had high casualty figures" and "There were more deaths in Korea" are the sort of phrasing used. Do not supply a number you have read elsewhere and present it as a Cambridge fact. It is not needed for any mark on this paper.

13. Quick revision

• The Key Question: how effectively did the United States contain the spread of communism? Three case studies only: Korea 1950 to 1953, Cuba 1959 to 1962, Vietnam 1955 to 1975.
• The unique structure: this is the only Key Question in Option B whose focus points are case studies rather than questions. Cambridge gives you the scope and leaves you to build the argument.
• Containment is defined narrowly: stop the spread, not roll back what is already communist. Designed by Truman. The test is the domino theory.
• Korea: invasion 25 June 1950; UN action possible because the Soviet delegate was absent; sixteen countries, American commander; Inchon, then Chinese intervention, then stalemate; MacArthur dismissed April 1951 for wanting a wider war; armistice July 1953, South Korea did not sign, demilitarised zone on the 38th Parallel. Success on containment, failure on unification.
• Cuba: Castro takes power 1959; Eisenhower's sanctions push Cuba toward the USSR; Castro declares himself communist 1960; Bay of Pigs 1961, 1400 exiles against 20,000 Cuban troops, a humiliation for Kennedy; Missile Crisis October 1962, thirteen days, quarantine, DEFCON 3, missiles removed for a no invasion pledge and a secret Turkish withdrawal; Khrushchev out of power 1964. Missiles removed, regime intact.
• Vietnam: French leave after Dien Bien Phu 1954; Kennedy's advisers, 11,000 by 1962; Gulf of Tonkin August 1964 and the Resolution; ground troops 1965; Rolling Thunder March 1965 to November 1968, over 800,000 tons; search and destroy, Agent Orange, napalm against tunnels, ambushes and the Ho Chi Minh Trail; Tet January 1968, over 120 attacks, a military defeat and a political disaster; My Lai, television, cost of $20 to $30 billion a year, the draft of 2.2 million, protests in 1969 and Kent State 1970; Vietnamisation, over 300,000 troops out between December 1970 and September 1972; Paris Peace Accords 1973, Kissinger signing; the South falls in 1975 and Laos and Cambodia follow.
• The verdict: contained in Korea, held in Cuba, lost in Vietnam. Say which weighting you are using and why. That sentence is the tenth mark.
• Where it appears: half of all Paper 1 papers, question 7 three times out of four, question 8 otherwise. Not a Paper 2 prescribed topic in 2027 or 2028.
• Never wander: origins of the Cold War is Key Question 4, Eastern Europe is Key Question 6.

Where these facts come from

History notes are only as good as their sourcing, so this section is deliberately explicit.

Taken from Cambridge's own published 0470 materials, meaning the syllabus for 2027 and 2028, the Paper 1 mark schemes for the March, June and November series from 2018 to 2024, and the Principal Examiner reports for the same period:

the Key Question, focus point and specified content wording, and the two printed forms of the Option B title; the Paper 2 prescribed topic lists for 2027 and 2028; the definition of containment and the point that it did not aim to roll back existing communist control; the domino theory and the countries named under it; the invasion of 25 June 1950 and the battle of Osan; the Security Council resolutions of June and July 1950 and the absence of the Soviet delegate; the sixteen contributing countries; MacArthur at Pusan, Inchon 200 miles behind enemy lines, the October 1950 advance and the April 1951 dismissal; the Chinese counter attack of January 1951; the July 1953 armistice, South Korea's refusal to sign, voluntary repatriation and the demilitarised zone; Kim Il-Sung's aims and Stalin's backing; Castro's background, the 1959 revolution and the 1960 declaration; Eisenhower's sanctions and support for an exile invasion; the Bay of Pigs, the CIA, the 1400 exiles and the 20,000 Cuban troops; the thirteen days, the quarantine, DEFCON 3, the U2, the two letters, the no invasion pledge, the secret Turkish withdrawal, the hotline and Khrushchev's fall in 1964; Khrushchev's three aims; Dien Bien Phu and the division of Vietnam; Kennedy's advisers and the 11,000 figure of 1962; the Strategic Hamlet programme; the Gulf of Tonkin incident of August 1964 and the Resolution; Operation Rolling Thunder, its dates and the 800,000 tons; search and destroy, Agent Orange and napalm; Vietcong tactics and the Ho Chi Minh Trail; the Tet Offensive, the 120 attacks, the Saigon embassy and Hue; the My Lai figures as printed; the $20 to $30 billion a year, the Life Magazine calculation of 1967, the 500,000 and 2 million troop figures, the 2.2 million draftees and the 25 per cent; the 1969 Washington demonstration and the four students shot in 1970; Walter Cronkite; Vietnamisation, "peace with honour" and the 300,000 troops withdrawn between December 1970 and September 1972; the Paris Peace Accords, Kissinger and the 60 day clause; and the fall of the South in 1975 with Laos and Cambodia following.

The question counts in section 3 were produced by reading all 48 Paper 1 mark schemes in the corpus for the 2018 to 2024 series and recording every question whose stem named Korea, Cuba, Vietnam or containment. They describe those 48 papers and are not a prediction.

Not verified against any Cambridge document, and therefore not stated as fact above:

• any casualty total for the Korean War or the Vietnam War, for any nationality
• the exact date in July 1953 of the armistice, and the exact date in October 1962 on which the missiles were discovered or removed
• the number of Soviet missiles or launch sites in Cuba
• the strength of Chinese forces in Korea, beyond the "almost 3 million troops and civilians" phrasing that appears in a single November 2019 mark scheme and nowhere else
• the number of American military personnel killed, and the number of names on any memorial
• the precise share of UN forces provided by the United States, which is disputed inside Cambridge's own documents and is covered in section 12
• the exact date of the Gulf of Tonkin incident within August 1964, and the exact date of the Tet Offensive within January 1968
• the exact death toll at My Lai, where Cambridge's own documents give both "300 villagers" and "hundreds"

None of those is needed for a top answer, which is why they have been left out of the body above rather than asserted.

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