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Wyatt's Notes — IB

The Cold War

The Cold War (1945—1991)

This document covers the IB History Cold War topic for Paper 2. It traces the development, escalation, and resolution of superpower rivalry between the United States and the Soviet Union, examining the major crises, periods of detente, and the eventual collapse of the Soviet bloc. Historiographical perspectives are integrated throughout to support high-scoring essay responses.

1. Origins of the Cold War

1.1 Yalta and Potsdam Conferences

The wartime alliance between the USA, UK, and USSR began to fracture even before the defeat of Nazi Germany. The conferences at Yalta (February 1945) and Potsdam (July—August 1945) exposed fundamental differences between the Allies over the post-war settlement of Europe.

Yalta Conference (4—11 February 1945)

  • Declaration on Liberated Europe: promised free elections in Eastern Europe
  • Division of Germany into four occupation zones (US, UK, France, USSR)
  • Soviet commitment to join the war against Japan within three months
  • Formation of the United Nations agreed
  • Stalin promised to allow free elections in Poland — a promise he later reneged on
  • The “percentages agreement” (Churchill—Stalin) divided spheres of influence in the Balkans

Potsdam Conference (17 July — 2 August 1945)

  • Truman replaced Roosevelt — harder anti-Soviet stance
  • Churchill replaced mid-conference by Attlee after Labour election victory
  • Atom bomb successfully tested during the conference — changed the power dynamic
  • Disagreement over Germany: Stalin wanted heavy reparations; the West wanted economic recovery
  • Disagreement over Poland: the Lublin government (Soviet-backed) vs the London government-in-exile
  • Reparations from each occupation zone, with the USSR receiving additional from the Western zones
  • Division of Germany into four zones confirmed; Berlin similarly divided despite being deep in the Soviet zone

1.2 The Truman Doctrine

On 12 March 1947, President Truman addressed Congress outlining what became known as the Truman Doctrine:

  • The USA would provide political, military, and economic assistance to all democratic nations under threat from authoritarian forces
  • Immediate context: Britain could no longer afford to support Greece against communist insurgents, and Turkey faced Soviet pressure on the Straits
  • $400 million in aid to Greece and Turkey
  • Marked the end of isolationist policy and the beginning of containment
  • The doctrine was ideological — it framed the conflict as a struggle between freedom and tyranny
  • It did not specifically name the USSR but was evidently directed against Soviet expansion

1.3 The Marshall Plan

Officially the European Recovery Programme (ERP), announced by Secretary of State George Marshall on 5 June 1947:

  • $13 billion in economic aid to Western European countries between 1948 and 1952
  • Aimed to rebuild war-damaged economies and prevent the spread of communism by reducing poverty and desperation
  • Conditional on cooperation between recipient nations and adoption of free-market policies
  • Stalin rejected the plan for the USSR and Eastern Europe, calling it “dollar imperialism”
  • The USSR established Comecon (Council for Mutual Economic Assistance) as a rival programme in 1949
  • The Marshall Plan was highly effective — Western European industrial production exceeded pre-war levels by 1952
  • It consolidated the division of Europe into Western and Soviet blocs

1.4 The Berlin Blockade and Airlift (1948—1949)

  • The Western Allies introduced a new currency (the Deutschmark) in their zones of Germany and Berlin (June 1948)
  • Stalin saw this as a threat to the Soviet economy and responded by blocking all road, rail, and canal access to West Berlin (24 June 1948)
  • 2.5 million people in West Berlin were cut off from supplies
  • The Western Allies responded with the Berlin Airlift — a massive operation to supply the city by air
    • At its peak, planes were landing in West Berlin every 30 seconds
    • Over 2 million tons of supplies were delivered
    • 277,000 flights over 462 days
  • Stalin lifted the blockade on 12 May 1949
  • The crisis led directly to the formal division of Germany:
    • Federal Republic of Germany (West Germany) established May 1949
    • German Democratic Republic (East Germany) established October 1949
  • NATO was formed partly in response to this crisis (see below)

1.5 NATO and Warsaw Pact Formation

NATO (North Atlantic Treaty Organisation)

  • Signed 4 April 1949 in Washington
  • Collective security organisation: an attack on one member is an attack on all (Article 5)
  • Original members: USA, UK, France, Canada, Italy, Belgium, Netherlands, Luxembourg, Denmark, Norway, Iceland, Portugal
  • West Germany joined in 1955 — this was a key trigger for the Warsaw Pact
  • First peacetime military alliance the USA had entered
  • Integrated military command under a Supreme Allied Commander (initially Eisenhower)
  • Demonstrated the USA”s commitment to defending Western Europe

Warsaw Pact

  • Signed 14 May 1955 in Warsaw
  • Collective security organisation for the Soviet bloc in response to West German rearmament and NATO
  • Members: USSR, Albania (withdrew 1968), Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, Romania
  • Provided a formal structure for Soviet control over Eastern European militaries
  • Allowed the USSR to maintain troops in Eastern Europe legally
  • Dissolved 31 March 1991

2. Key Crises

2.1 The Korean War (1950—1953)

  • Korea divided at the 38th parallel after WWII: Soviet north, US south
  • North Korean forces invaded South Korea on 25 June 1950, led by Kim Il-sung with Soviet backing
  • The UN Security Council authorised military intervention (the USSR was boycotting the Council and could not veto)
  • UN forces (predominantly American) under MacArthur pushed North Korean forces back to the Yalu River
  • China entered the war in October 1950 when UN forces approached the Yalu — 300,000 Chinese troops crossed the border
  • The war became a stalemate around the 38th parallel
  • MacArthur wanted to use nuclear weapons against China; Truman dismissed him (April 1951)
  • Armistice signed 27 July 1953 — Korea remained divided at approximately the 38th parallel
  • Casualties: approximately 5 million, mostly Korean civilians
  • Significance: first “hot war” of the Cold War; demonstrated the limits of containment; China emerged as a major Cold War actor

2.2 Hungarian Uprising (1956)

  • Stalin died in 1953; Khrushchev’s “Secret Speech” (February 1956) denounced Stalin’s crimes
  • This encouraged reform movements across Eastern Europe
  • In Hungary, reformist leader Imre Nagy was appointed Prime Minister (October 1956)
  • Nagy announced sweeping reforms:
    • Withdrawal from the Warsaw Pact
    • Free elections
    • Restoration of a multi-party system
    • Request for UN mediation
  • The Soviet Union responded with a massive military invasion on 4 November 1956
    • 200,000 Soviet troops and 2,500 tanks entered Hungary
    • Nagy was arrested, tried, and executed in 1958
    • Kadar was installed as the new Soviet-aligned leader
  • The West condemned the invasion but did not intervene militarily
  • The Suez Crisis occurred simultaneously — distracting Western attention
  • Significance: demonstrated that the USSR would use force to maintain control of the Eastern bloc; confirmed the limits of Western intervention behind the Iron Curtain

2.3 Berlin Wall (1961)

  • Between 1949 and 1961, approximately 2.5 million East Germans fled to the West, many through Berlin
  • This “brain drain” of skilled workers severely damaged the East German economy
  • Khrushchev gave East German leader Walter Ulbricht permission to close the border
  • Construction of the Berlin Wall began on 13 August 1961
    • Initially barbed wire and concrete blocks; gradually reinforced into a sophisticated barrier
    • 155 km of fortifications including a “death strip”
    • Guard towers, anti-vehicle trenches, floodlights
  • The Wall became the most powerful symbol of the Cold War division of Europe
  • Kennedy’s famous response: “Ich bin ein Berliner” (26 June 1963)
  • At least 140 people died attempting to cross the Wall
  • The Wall stabilised East Germany by preventing further mass emigration
  • It also reduced Cold War tensions in the short term by removing Berlin as a crisis flashpoint

2.4 Cuban Missile Crisis (1962)

The closest the world came to nuclear war.

Background

  • Fidel Castro overthrew the Batista regime in Cuba (1959) and established a communist government
  • The USA attempted to overthrow Castro through the Bay of Pigs invasion (April 1961) — a failed CIA-backed invasion by Cuban exiles
  • In response, Castro moved closer to the USSR
  • The USSR installed nuclear missiles in Cuba (Operation Anadyr) in May—October 1962

The Crisis (16—28 October 1962)

  • U-2 spy planes discovered Soviet missile sites under construction in Cuba (14 October)
  • Kennedy imposed a naval “quarantine” (blockade) of Cuba on 22 October
  • Soviet ships approached the quarantine line
  • For several days, the world stood on the brink of nuclear war
  • Intense negotiations between Kennedy and Khrushchev
  • Secret agreement: Kennedy would remove US Jupiter missiles from Turkey (to be completed within 6 months)
  • Public agreement: USSR would remove missiles from Cuba; USA would pledge not to invade Cuba
  • The crisis ended on 28 October when Khrushchev announced the removal of Soviet missiles

Significance

  • Direct communication hotline between Washington and Moscow established (1963)
  • Both leaders recognised the need for arms control — led to the Partial Test Ban Treaty (1963)
  • Khrushchev was seen as backing down — contributed to his ousting in 1964
  • Demonstrated the dangers of nuclear brinkmanship and miscalculation
  • Reinforced the concept of mutually assured destruction (MAD)

2.5 Prague Spring (1968)

  • Alexander Dubcek became leader of Czechoslovakia in January 1968
  • He launched a programme of reforms known as “socialism with a human face”:
    • Freedom of speech and the press
    • Freedom of movement and travel
    • Economic reforms introducing market elements
    • Reduction in censorship
    • “Two thousand words” manifesto (June 1968) called for further democratisation
  • The Brezhnev Doctrine was articulated in response: the USSR had the right to intervene in any socialist country where socialism was threatened
  • Warsaw Pact forces invaded Czechoslovakia on 20—21 August 1968
    • 500,000 troops from the USSR, Bulgaria, East Germany, Hungary, and Poland
    • Dubcek was arrested and taken to Moscow; he was replaced by Husak
    • Czechoslovakia returned to orthodox communism
  • Civilian resistance was non-violent — the “Prague Spring” became a symbol of peaceful resistance
  • The Brezhnev Doctrine was used to justify the suppression of any reform movement in the Eastern bloc
  • Significance: demonstrated that the USSR would not tolerate reform even when it was popular and internally driven; reinforced the division of Europe

2.6 Soviet Invasion of Afghanistan (1979)

  • Afghanistan had a pro-Soviet government after a 1978 coup
  • Growing resistance from Islamic Mujahideen rebels
  • The Soviet Union invaded Afghanistan on 24 December 1979
    • 100,000 Soviet troops entered the country
    • Installed Babrak Karmal as the new leader
    • Aimed to prop up the communist government and prevent Islamic fundamentalism from spreading to the Soviet Central Asian republics
  • The Mujahideen received support from the USA, Pakistan, Saudi Arabia, and China (Operation Cyclone)
    • CIA supplied Stinger missiles which were effective against Soviet helicopters
  • The war became a “Soviet Vietnam” — a long, costly, and unpopular conflict
    • Approximately 15,000 Soviet soldiers killed
    • Over 1 million Afghan civilians killed
    • 5 million Afghan refugees fled to Pakistan and Iran
  • Gorbachev withdrew Soviet troops between 1988 and 1989 (completed February 1989)
  • The war destabilised the region and contributed to the rise of the Taliban
  • Significance: ended the period of detente; led to a renewed arms race; demonstrated the limits of Soviet power; contributed to the economic strain that would eventually undermine the USSR

3. Detente

3.1 SALT Treaties

  • SALT I (1972): Strategic Arms Limitation Talks — first agreement between USA and USSR to limit strategic nuclear weapons
    • Anti-Ballistic Missile (ABM) Treaty: limited each side to two ABM systems (later reduced to one)
    • Interim Agreement: froze the number of ICBMs and SLBMs at existing levels
    • Did not reduce existing arsenals but established the principle of arms control
    • Demonstrated that both superpowers recognised the danger of unconstrained arms racing
  • SALT II (1979): Further limitations on strategic weapons
    • Signed by Carter and Brezhnev but never ratified by the US Senate
    • Soviet invasion of Afghanistan (December 1979) ended any chance of ratification
    • Both sides informally observed its provisions until 1986

3.2 Helsinki Accords (1975)

  • Signed on 1 August 1975 by 35 nations (USA, Canada, USSR, and most European states)
  • Three “baskets”:
    1. Security: recognition of post-WWII European borders (the USSR gained formal recognition of its territorial gains)
    2. Cooperation: economic, scientific, and technological cooperation
    3. Human Rights: fundamental freedoms, including freedom of thought, conscience, and religion
  • Basket Three became a powerful tool for dissident movements in Eastern Europe (e.g., Charter 77 in Czechoslovakia, Helsinki monitoring groups in the USSR)
  • The Helsinki Final Act established the Conference on Security and Cooperation in Europe (CSCE), later the Organisation for Security and Cooperation in Europe (OSCE)

3.3 Nixon’s Visit to China (1972)

  • Nixon visited China 21—28 February 1972 — the first US president to visit the People’s Republic
  • Secret diplomacy conducted by Henry Kissinger and Zhou Enlai in 1971 paved the way
  • The Shanghai Communique outlined shared interests in opposing Soviet hegemony
  • Ping-pong diplomacy (1971) helped break the ice
  • China was admitted to the UN in 1971, replacing Taiwan
  • The visit exploited the Sino-Soviet split and put pressure on the USSR
  • Significance: shifted the global balance of power; initiated China’s integration into the international system; demonstrated the complexity of Cold War alliances

3.4 Nuclear Arms Control

  • The concept of MAD (Mutually Assured Destruction) underpinned arms control logic
  • If both sides possessed an assured second-strike capability, neither could launch a first strike
  • This created a stable but terrifying equilibrium
  • Arms control agreements aimed to:
    • Limit the number and types of weapons
    • Prevent the development of new delivery systems
    • Reduce the risk of accidental nuclear war
    • Build trust and communication between the superpowers
  • The Partial Test Ban Treaty (1963) banned nuclear testing in the atmosphere, space, and underwater
  • The Nuclear Non-Proliferation Treaty (NPT, 1968) aimed to prevent the spread of nuclear weapons

3.5 Ostpolitik

  • West German Chancellor Willy Brandt’s policy of normalisation with Eastern Europe (1969—1974)
  • “Change through rapprochement” — engaging with communist states to encourage reform
  • Key agreements:
    • Treaty of Moscow (1970): recognised post-war borders, renounced use of force
    • Treaty of Warsaw (1970): recognised the Oder-Neisse line as Poland’s western border
    • Basic Treaty with East Germany (1972): recognised the GDR as a sovereign state (while maintaining the goal of German reunification)
  • Brandt won the Nobel Peace Prize in 1971
  • Ostpolitik reduced tensions in Europe and facilitated the Helsinki process
  • Critics argued it legitimised the division of Germany and the Soviet domination of Eastern Europe

4. End of the Cold War

4.1 Gorbachev’s Reforms

Mikhail Gorbachev became General Secretary of the Communist Party in March 1985.

Glasnost (“Openness”)

  • Relaxation of censorship and increased freedom of speech
  • Allowed open discussion of previously taboo topics: Stalin’s purges, the Chernobyl disaster (April 1986), economic failures
  • Enabled the emergence of dissident movements and nationalist organisations
  • Unintended consequence: exposed the incompetence and corruption of the Soviet system, undermining legitimacy

Perestroika (“Restructuring”)

  • Economic reforms to address stagnation:
    • Introduction of limited market mechanisms
    • Reduction of central planning
    • Encouragement of small private enterprises (cooperatives)
    • Enterprise autonomy — factories given more control over production
  • Political reforms:
    • Introduction of competitive elections (albeit within a one-party framework initially)
    • Creation of a new parliament, the Congress of People’s Deputies (1989)
    • Gorbachev became President of the USSR in 1990
  • Perestroika was half-hearted and poorly implemented — it created uncertainty without delivering improvements
  • Combined with glasnost, it unleashed forces Gorbachev could not control

4.2 Fall of the Berlin Wall (9 November 1989)

  • Mass protests in East Germany throughout 1989
  • Hungary opened its border with Austria (May 1989), allowing East Germans to escape to the West
  • Hundreds of thousands of East Germans fled through Hungary and Czechoslovakia
  • Mass demonstrations in Leipzig (“Monday demonstrations”) grew from hundreds to hundreds of thousands
  • Gorbachev visited East Berlin in October 1989 and stated that each country should follow its own path — implicitly rejecting the Brezhnev Doctrine
  • East German leader Honecker was replaced by Krenz in October 1989
  • On 9 November 1989, an ill-prepared press conference by Gunter Schabowski led to the borders being opened
  • Thousands of East Berliners flooded through the checkpoints
  • People began demolishing the Wall with hammers and pickaxes (“Mauerspechte” — wall woodpeckers)
  • The fall of the Wall symbolised the collapse of communism in Eastern Europe

4.3 Reunification of Germany (1990)

  • Helmut Kohl announced a ten-point plan for German reunification (November 1989)
  • The “Two Plus Four” negotiations: the two Germanys plus the four wartime powers (USA, USSR, UK, France)
  • Treaty on the Final Settlement with Respect to Germany (12 September 1990):
    • Germany regained full sovereignty
    • Confirmed Germany’s existing borders (Oder-Neisse line)
    • Germany agreed to limit its military to 370,000 troops
    • Soviet troops to withdraw from East Germany by 1994
  • Germany was formally reunited on 3 October 1990
  • East Germany was absorbed into the Federal Republic
  • Significance: the most dramatic symbol of the end of the Cold War; raised fears of German dominance in Europe but ultimately stabilised under NATO and EU membership

4.4 Dissolution of the USSR

  • The Baltic republics (Estonia, Latvia, Lithuania) declared independence (1990—1991)
  • The August Coup (19—21 August 1991):
    • Hardline communists attempted to overthrow Gorbachev
    • The coup failed after Boris Yeltsin rallied opposition from the Russian parliament building
    • Gorbachev returned to power but was fundamentally weakened
  • Yeltsin emerged as the dominant figure in Russian politics
  • The Communist Party was banned
  • The USSR was formally dissolved on 26 December 1991
    • The Commonwealth of Independent States (CIS) replaced it as a loose association
    • 15 independent republics emerged
  • The Cold War was over

5. Historiographical Debates

5.1 Orthodox, Revisionist, and Post-Revisionist Interpretations

Orthodox (Traditionalist) School

  • Dominant in the USA during the 1950s and 1960s
  • Places primary responsibility for the Cold War on the USSR and Stalin’s expansionist ambitions
  • Stalin’s ideology of world revolution and the inherent aggressiveness of communism were the driving forces
  • The USA was forced into a defensive posture by Soviet aggression
  • Key historians: George Kennan, Arthur Schlesinger Jr., Herbert Feis

Revisionist School

  • Emerged in the 1960s and 1970s, influenced by the Vietnam War and critical views of US foreign policy
  • Places primary responsibility on the USA and American capitalism’s need for global markets
  • The USSR was primarily defensive, reacting to American economic imperialism and nuclear intimidation
  • The Marshall Plan was economic aggression; NATO was a provocative military alliance
  • The USA used atomic diplomacy to intimidate the USSR
  • Key historians: William Appleman Williams, Gabriel Kolko, Gar Alperovitz

Post-Revisionist School

  • Emerged in the late 1970s and 1980s
  • Seeks a balanced view: both sides contributed to the Cold War through mutual misunderstanding, ideological differences, and security dilemmas
  • Emphasises the role of misperception, bureaucratic politics, and structural factors
  • The Cold War was not the result of a single villain but of a complex system of competing interests
  • Key historians: John Lewis Gaddis (early work), Melvyn Leffler

5.2 Responsibility for Cold War Origins

  • Was the Cold War inevitable? Structuralists argue that two ideologically opposed superpowers with competing visions for the post-war world would inevitably clash
  • Could it have been avoided? Contingentists point to specific decisions and missed opportunities: Roosevelt’s death, the bomb, Stalin’s intransigence
  • The opening of Soviet archives after 1991 provided new evidence but did not produce a single definitive answer

5.3 Inevitability of Soviet Collapse

  • Internalist arguments: The Soviet economy was unsustainable; the command economy could not compete with Western capitalism; Gorbachev’s reforms accelerated an inevitable collapse
  • Externalist arguments: The arms race (particularly Reagan’s military build-up and SDI) bankrupted the Soviet economy; the Afghanistan war drained resources; Western pressure forced the USSR to the negotiating table
  • Accidental collapse argument: Gorbachev did not intend to destroy the Soviet system; his reforms unleashed nationalist forces that spiralled beyond control

6. Essay Writing Tips

  1. Establish clear timelines: Cold War questions often span decades. Chronological structure works well — show change over time rather than treating events as isolated incidents.
  2. Evaluate causation: Avoid listing events. For each crisis, identify causes, course, and consequences — and explain their relative significance.
  3. Use historiography deliberately: Don’t just name historians. Explain how their interpretations differ and why, then take a reasoned position.
  4. Balance depth and breadth: The IB rewards detailed knowledge of specific events combined with awareness of the broader Cold War context.
  5. Consider multiple perspectives: Always address both superpower perspectives. Soviet motivations (security, ideology, historical experience of invasion) are just as important as American ones.
  6. Link crises: Show how events influenced each other. The Hungarian Uprising affected the Cuban Missile Crisis; the Suez Crisis distracted from Hungary; Afghanistan ended detente.
  7. Define terms: Concepts like “containment”, “detente”, “brinkmanship” and “domino theory” should be precisely defined and applied.

7. Common Pitfalls

  1. Presenting the Cold War as a simple binary: The reality was far more complex, involving intermediate powers, economic factors, and internal dynamics within both blocs.
  2. Anachronism: Judging past actions with present knowledge. The fear of communism in the 1950s was genuine and had historical roots, even if it seems exaggerated in retrospect.
  3. Ignoring the Third World: Cold War competition in Africa, Asia, and Latin America was central, not peripheral. Proxy wars were a defining feature.
  4. Confusing correlation with causation: Just because two events happened in sequence does not mean one caused the other. Always assess the relationship critically.
  5. Overstating Soviet unity: The Eastern bloc was not monolithic. Tito’s Yugoslavia, Sino-Soviet split, and Romanian independence demonstrate significant variation.
  6. Neglecting economic factors: The Cold War was fundamentally an economic competition. Arms spending, trade policy, and economic performance were crucial.
  7. Writing a narrative instead of an argument: Essays must have a clear thesis supported by evidence, not directly tell the story of the Cold War chronologically.

8. Summary

The Cold War was a global struggle between two ideologically opposed superpowers that shaped international relations for nearly half a century. It began from the breakdown of the wartime alliance and competing visions for the post-war order, manifested through a series of crises that brought the world to the brink of nuclear war, and ended with the collapse of the Soviet system under the weight of its own contradictions and the pressures of reform. The historiographical debate remains alive: orthodox, revisionist, and post-revisionist interpretations continue to offer competing explanations for the origins, course, and conclusion of the conflict.

Worked Examples

Worked examples demonstrating the application of key concepts are covered in the detailed sub-pages linked above.