The Precarious Foundations of Wartime Cooperation

The Second World War witnessed an unprecedented alliance between Western democracies and the Soviet Union, united against the common threat of Nazi Germany. As Stalin remarked during the Yalta Conference, maintaining solidarity during war proved simpler than preserving it afterward. This observation foreshadowed the tensions that would unravel the Grand Alliance once victory was secured.

Unlike the revolutionary wave that followed World War I, postwar Europe in 1945 remained politically stable despite catastrophic devastation. The continent’s exhaustion played a key role—civilian deaths reached 34.3 million, including 6 million Jews, while military fatalities exceeded 16.9 million. Material losses were 13 times greater than in 1918. With 30 million Europeans displaced in the war’s first three years alone, societies were too shattered to contemplate revolution.

Another stabilizing factor was the Allied occupation. Soviet, British, and American forces suppressed unrest, ensuring no grassroots upheavals. Any political transformations in Eastern Europe were dictated from Moscow, not driven by local movements. This top-down control allowed the Allies to shape Europe’s postwar trajectory—but also sowed seeds of discord.

From Cooperation to Confrontation: Key Turning Points

Initially, the Allies demonstrated remarkable unity. Churchill famously declared support for the USSR after Hitler’s invasion in June 1941, stating, “The Russian danger is our danger.” Concrete collaborations followed: the Atlantic Charter (August 1941), the Anglo-Soviet Treaty (May 1942), and Lend-Lease agreements. Even the dissolution of the Communist International in 1943—a symbolic gesture toward Western sensitivities—highlighted wartime pragmatism.

However, cracks emerged as victory neared. The 1944 Moscow Percentages Agreement, where Churchill and Stalin informally divided Balkan influence, revealed competing postwar visions. Britain secured Greece, while Romania and Bulgaria fell under Soviet sway. When British forces later clashed with Greek communist partisans, Stalin honored this backroom deal by remaining passive—expecting reciprocal Western tolerance of his Eastern European dominance.

The February 1945 Yalta Conference marked the alliance’s zenith but also its unraveling. While agreements on Germany’s occupation and Polish borders appeared harmonious, the Declaration on Liberated Europe—pledging free elections—masked irreconcilable interpretations. Stalin viewed it as mere rhetoric, while the U.S. took it literally. By Potsdam (July-August 1945), Stalin bluntly stated that freely elected Eastern European governments would be anti-Soviet, making them unacceptable.

The Institutional Legacy: United Nations and Early Cold War Frameworks

Amid growing tensions, the Allies established the United Nations in June 1945. Modeled after the League of Nations, it aimed to prevent conflict through collective security while addressing global socioeconomic issues. The Security Council’s veto power for permanent members (the U.S., USSR, Britain, France, and China) acknowledged great-power realities. Though successful in non-political realms like health and education, the UN struggled to mediate Cold War disputes, from Korea to Vietnam.

Meanwhile, Europe’s division hardened. The 1947 Truman Doctrine and Marshall Plan ($12.5 billion in aid) countered Soviet expansion, prompting Moscow’s Molotov Plan. By 1949, rival military blocs emerged: NATO and the Warsaw Pact (1955). Similar fractures appeared in Asia, where Mao’s 1949 victory in China and the Korean War (1950-1953) expanded Cold War battlegrounds.

The Cold War’s Unexpected Collapse

Détente began tentatively after Stalin’s death (1953) and the Korean Armistice. The 1962 Cuban Missile Crisis—resolved through backchannel negotiations—spurred arms control agreements, including the 1963 Test Ban Treaty. However, the Cold War’s abrupt end in the late 1980s surprised observers. The USSR’s economic stagnation and internal fractures led to its dissolution, while China’s post-Mao economic reforms created a new geopolitical dynamic.

The Sino-Soviet split, fueled by border disputes and ideological differences (Mao’s egalitarian communism versus Soviet bureaucratic socialism), further transformed Cold War alignments. By the 1990s, the binary superpower struggle had given way to a multipolar world—one still grappling with the legacy of that fragile wartime alliance and its fraught aftermath.

In retrospect, World War II’s Grand Alliance was always a marriage of convenience. Once the common enemy vanished, divergent interests and mutual suspicions prevailed—proving Stalin’s cynical prediction tragically accurate.