Explain the origins of the Cold War, including the wartime alliances and tensions between the USA and USSR, the Yalta and Potsdam conferences, the Truman Doctrine, the Marshall Plan, and the division of Germany and Berlin

What this dot point is asking

QCAA wants you to explain the origins of the Cold War (1945 to 1949): the breakdown of the wartime alliance, the conferences at Yalta and Potsdam, the practical division of Europe by the Red Army's advance and the Western Allies' occupation zones, the early US containment policies (Truman Doctrine, Marshall Plan), the division of Germany and Berlin, and the formation of NATO. The dot point underpins IA1 / IA2 / IA3 essays on the Cold War's causation and is a recurring EA short-response prompt.

The answer

The Cold War was the post-war confrontation between the USA and USSR (and their allies) that dominated international politics from 1945 to 1991. Its origins lie in the breakdown of the wartime alliance, the bipolar power structure left by the Second World War, the ideological gulf between liberal capitalism and Stalinist communism, and the specific events of 1945-1949 that institutionalised the divide.

The wartime alliance and its tensions

The USA, USSR and Britain were allies only because of the common enemy of Nazi Germany. The alliance was instrumental from the start.

• Underlying ideological conflict. Capitalist USA and communist USSR had been opponents since the Bolshevik Revolution (1917). The USA delayed diplomatic recognition until 1933.
• Wartime tensions. Delays in opening the Western Front (Soviet pressure for D-Day was finally answered in June 1944). The Manhattan Project's secrecy from the USSR. Roosevelt and Stalin developed personal rapport at Tehran (1943) and Yalta (Feb 1945), but Truman (after Roosevelt's death in April 1945) inherited a less personal relationship and arrived at Potsdam (July-August 1945) with a more confrontational stance, partly informed by the impending atomic test (Trinity, July 16, 1945).

The Yalta and Potsdam conferences

Yalta (Feb 1945). Roosevelt, Stalin, Churchill agreed:

• The post-war zones of occupation in Germany (US, UK, French, Soviet).
• A four-power occupation of Berlin (despite Berlin lying inside the Soviet zone).
• Free elections in Poland and Eastern Europe.
• Soviet entry into the war against Japan in exchange for territorial concessions.

The "free elections" commitment proved decisive in the breakdown: the USSR never permitted free elections in its sphere.

Potsdam (July-August 1945). Truman, Stalin, Attlee (who replaced Churchill mid-conference). Confirmed German zone arrangements. Approved reparations from the Soviet zone. The atomic bomb was successfully tested during the conference; Truman informed Stalin of "a new weapon of unusual destructive force" without specifying. The atomic monopoly (USA only, until August 1949) coloured American confidence; Soviet espionage (Klaus Fuchs and others) was already at work.

The atomic monopoly and the bomb

The dropping of the atomic bombs on Hiroshima (August 6, 1945) and Nagasaki (August 9, 1945) ended the Pacific war and demonstrated American military supremacy. Some historians (Gar Alperovitz, revisionist) argue the bombs were partly directed at the USSR as a diplomatic signal; others (orthodox) emphasise the military rationale of ending the war quickly to avoid invasion. The USSR developed its own atomic bomb by August 1949, ending the US monopoly and entering the era of nuclear parity that would shape every subsequent crisis.

The division of Europe (1945-1947)

By the end of 1945, the Red Army occupied Eastern Europe. The Western Allies occupied Western Europe. The practical division was set by the meeting of forces in May 1945. Free elections in Hungary (1945), Poland (1946-47), Romania, Bulgaria and Czechoslovakia were progressively undermined by Soviet-backed communist parties. By 1947-48, all Eastern European states had communist governments installed.

Churchill's "Iron Curtain" speech (Fulton, Missouri, March 5, 1946) named the division: "from Stettin in the Baltic to Trieste in the Adriatic, an iron curtain has descended across the Continent." The phrase entered the diplomatic vocabulary.

Containment: the Truman Doctrine and Marshall Plan

The American policy response was containment, formulated initially by George Kennan in the "Long Telegram" (Feb 1946) and the anonymous "X" article in Foreign Affairs (July 1947).

Truman Doctrine (March 12, 1947). In a speech to Congress, Truman pledged American support for "free peoples who are resisting attempted subjugation by armed minorities or by outside pressures". The immediate context was Greece and Turkey (where Britain could no longer afford to support anti-communist governments), but the doctrine framed the entire Cold War.

Marshall Plan (June 5, 1947 to 1952). Secretary of State George Marshall proposed economic aid to rebuild war-damaged Europe. The USA disbursed about $13 billion (around$130 billion in 2020 terms) across 16 Western European countries. The aid was offered to Eastern Europe as well, but Stalin forbade acceptance; the plan therefore consolidated the economic division of Europe.

The Berlin Blockade and Airlift (June 1948 to May 1949)

The Western Allies (USA, UK, France) merged their occupation zones in Germany (Bizonia by 1947, Trizonia by 1948) and introduced a new currency (Deutschmark) in their sectors and in West Berlin. Stalin responded by blockading all road, rail and canal access to West Berlin from June 24, 1948.

The Western response was an unprecedented airlift: at peak, over 1,000 flights per day delivered food, fuel and supplies to West Berlin's 2 million people. The airlift lasted 11 months. Stalin lifted the blockade on May 12, 1949, conceding without firing a shot.

The blockade and airlift were the first major Cold War confrontation. They demonstrated American resolve and capability and accelerated:

• The founding of NATO (April 4, 1949).
• The establishment of the Federal Republic of Germany (West Germany, May 23, 1949).
• The establishment of the German Democratic Republic (East Germany, October 7, 1949).

NATO (April 4, 1949)

The North Atlantic Treaty Organization united 12 founding members (USA, Canada, UK, France, Belgium, Netherlands, Luxembourg, Norway, Denmark, Iceland, Portugal, Italy) in a mutual-defence pact. Article 5 ("an armed attack against one or more of them... shall be considered an attack against them all") formalised American military commitment to Western European defence. The Soviet response, the Warsaw Pact, was not formed until 1955 (after West Germany joined NATO).

Historiographical interpretations

QCAA Modern History rewards engagement with historiography. The Cold War's origins have been interpreted three main ways:

Orthodox (1950s-1960s). The USSR was the primary cause. Stalin's expansionism in Eastern Europe forced American containment. Schlesinger, Feis, Bemis.

Revisionist (1960s-1970s, partly responding to Vietnam). The USA was equally or more responsible. American economic interests, atomic diplomacy, and aggressive containment escalated tensions. Williams, Kolko, Alperovitz.

Post-revisionist (1970s onwards). Both sides bear responsibility. Misperception, structural bipolarity, and ideological incompatibility produced the conflict; specific events became the catalysts. Gaddis, LaFeber.

Strong IA1 / IA2 essays acknowledge the historiographical debate; strong EA short responses cite specific dates and events.

In one sentence

The Cold War's origins (1945 to 1949) lie in the breakdown of the wartime alliance amid bipolar power, the failure of Yalta promises of free elections in Eastern Europe, the American policies of containment (Truman Doctrine 1947, Marshall Plan 1947) responding to perceived Soviet expansion, the formal division of Germany and Berlin culminating in the Berlin Blockade and Airlift (1948 to 1949), and the institutionalisation of the divide through NATO (April 1949) and the founding of the two German states (1949).