Topic 7.14 Notes – Postwar Diplomacy

How World War II Made the United States the Leading Global Power

By 1945, the U.S. stood in a position no country had held before. Europe and much of Asia were wrecked by bombing, invasion, and mass death. The map helps show the scale of destruction and occupation in Europe at the war’s height. The continental United States was largely untouched, so its factories, farms, and transportation systems were still working at full strength.

Europe at the height of German expansion, 1941-1942

• Wartime mobilization ended Depression-era unemployment and turned the U.S. into the arsenal of democracy, supplying weapons and goods on a huge scale.
• By the end of the war, the U.S. produced about half of the world’s manufactured goods and held major financial reserves.
• Its military power was unmatched. It had the strongest navy and air force, troops around the world, and the ability to fight in Europe and the Pacific at the same time.
• The U.S. also had a temporary atomic monopoly until the Soviet bomb test in 1949.

This changed foreign policy. After World War I, the Senate rejected the League of Nations and the U.S. pulled back from permanent commitments. After World War II, that kind of limited role no longer made sense because the U.S. now had the power, wealth, and global reach to shape the postwar world.

The Main Parts of the Postwar Settlement

The postwar settlement fits into four connected pieces. Allied leaders bargained at wartime conferences, built the United Nations, created a new global economic system, and occupied former Axis states. All of it aimed to prevent another world war, but it also protected American power and interests.

Yalta and Potsdam

At Yalta in February 1945, Franklin Roosevelt, Winston Churchill, and Joseph Stalin tried to plan the peace before Germany surrendered.

• Germany and Berlin were divided into four occupation zones.
• Stalin promised to join the war against Japan.
• In the Declaration on Liberated Europe, Stalin also promised free elections in Eastern Europe.
• The voting structure of the United Nations, including the permanent-member veto, was finalized.

A common AP mistake is treating Yalta like complete agreement. It was a compromise with vague wording, especially over Eastern Europe, so each side could claim it meant something different later.

At Potsdam in July-August 1945, Harry Truman, Stalin, and Churchill/Clement Attlee met after Germany had surrendered.

• They confirmed the occupation of Germany and the four Ds: demilitarization, denazification, democratization, decentralization.
• Arguments over reparations, Poland, and Eastern Europe showed the alliance was already weakening.
• The Potsdam Declaration demanded Japan’s unconditional surrender.
• Truman’s position was stronger because the U.S. had just successfully tested the atomic bomb.

The United Nations

The United Nations showed that the U.S. had accepted permanent international leadership.

• Created in 1945 with strong U.S. backing; Senate approved membership 89-2
• Goals included collective security, diplomacy, cooperation, and human rights
• General Assembly = all member states
• Security Council = five permanent members with veto power
  • United States
  • Soviet Union
  • Britain
  • France
  • China
• Headquarters in New York City
• Universal Declaration of Human Rights in 1948, drafted with major help from Eleanor Roosevelt

Bretton Woods and the postwar economy

The U.S. also shaped the rules of global capitalism.

• Bretton Woods Conference in 1944 created a dollar-centered system
• Fixed exchange rates were tied to the dollar, and the dollar was convertible to gold at $35 per ounce
• IMF gave short-term aid and helped stabilize exchange rates
• World Bank funded reconstruction and development
• GATT in 1947 lowered trade barriers

This system promoted stable currencies and open trade, but it also locked in American financial dominance.

How the United States Reshaped Germany and Japan

Victory gave the U.S. and its allies the power to rebuild defeated enemies.

• Germany was divided into U.S., British, French, and Soviet zones; Berlin was also divided. Austria and Vienna were divided too. The goals were disarmament, destroying Nazism, prosecuting war criminals, decentralizing power, and building democracy. A major fight appeared quickly. The Soviets wanted heavy reparations, while the U.S. and Britain increasingly wanted German recovery.
• Japan was occupied mainly by the U.S. under Douglas MacArthur and, unlike Germany, was not split into zones. The 1947 constitution created parliamentary democracy, civil liberties, women’s rights, and universal suffrage. Article 9 renounced war. Land reform and attacks on industrial conglomerates tried to weaken militarism. Emperor Hirohito stayed, but gave up divine status and lost direct political power.

War Crimes, Nuclear Power, and the Road to the Cold War

Postwar justice and postwar tension developed at the same time.

• Nuremberg Trials prosecuted Nazi leaders for crimes against peace, war crimes, and crimes against humanity. The lasting principle was individual responsibility under international law.
• Tokyo Trials prosecuted Japanese leaders for aggressive war and atrocities. Hirohito was not tried, which shows diplomacy could shape justice.

Atomic weapons gave the U.S. huge leverage, but they also made the Soviets fear American power even more. The deepest disagreements were over Eastern Europe, Poland, reparations, Germany, and whether postwar governments should reflect self-determination or Soviet security needs.