Old Friends Become New Enemies

Even before World War II ended, the friendship between the U.S. and the Soviet Union started to break down. The U.S. was angry that Joseph Stalin, the leader of the Soviet Union, had made a deal with Germany in 1939 not to fight each other. Later, Stalin said it was the fault of the other countries (the Allies) that they didn't attack German-controlled Europe sooner, before 1944. Because of these and other disagreements, the two countries started wanting different things.

Yalta Conference: Planning for After the War

In February 1945, the war was still going on. But the leaders of the United States, Great Britain, and the Soviet Union met in Yalta, a place in the Soviet Union by the Black Sea. There, they agreed to split Germany into different parts that would be controlled by the Allied armies. Germany also had to pay the Soviet Union for all the people who died and the things that were destroyed. Stalin also said he would join the fight against Japan. He also promised that the countries in Eastern Europe would have free elections (where people could vote for who they wanted). But Winston Churchill, the leader of Great Britain, didn't really believe Stalin. He thought Stalin would only keep his promise if those Eastern European countries did what Russia wanted.

The United Nations is Created

In June 1945, the United States and the Soviet Union decided to put their differences aside for a little while. They joined with 48 other countries to create the United Nations (UN). This was a group of countries that wanted to protect each other from being attacked. The UN would have its main office in New York.

The rules for the UN said there would be a big group called the General Assembly. In this group, every country in the UN could vote on different topics. But the real power to solve problems was in a smaller group called the Security Council, which had 11 members. Five of these members were always the same: Great Britain, China, France, the United States, and the Soviet Union. These five countries could stop any action the Security Council wanted to take by saying "no" (this is called a veto). This rule was made so that no group of countries on the Council could boss the others around.

The U.S. and Soviet Union Want Different Things

Even though the U.S. and the Soviet Union had agreed on some things at Yalta and were both part of the Security Council, they started to disagree a lot after the war. The war had affected them in very different ways. The United States was the richest and most powerful country in the world, and about 400,000 Americans had died. But the cities and factories in the U.S. were still in good shape. The Soviet Union, on the other hand, had lost way more people – maybe 50 times as many. One out of every four people in the Soviet Union had been hurt or killed. Also, many cities in the Soviet Union were destroyed. These different situations, along with their different ideas about politics and money, made the two countries want different things after the war.

The Iron Curtain in Eastern Europe

One of the main things the Soviet Union wanted was to protect itself from being invaded again from the west. Throughout history, the Soviet people had learned to be afraid of invasions. Because the western side of Russia didn't have natural barriers like mountains or big rivers, it was easy for other countries to attack. In the 1600s, Poland captured the Kremlin (the main government building in Russia). In the 1700s, Sweden attacked. Napoleon's army took over Moscow in 1812. And Germany invaded Russia during both World War I and World War II.

The Soviets Create a Buffer Zone

As World War II was ending, Soviet soldiers pushed the German army back across Eastern Europe. When the war was over, these soldiers were in control of a line of countries along the Soviet Union's western border. Stalin saw these countries as a buffer, like a wall that would protect the Soviet Union. He ignored the agreement made at Yalta and put Communist governments in charge in Albania, Bulgaria, Hungary, Czechoslovakia, Romania, Poland, and Yugoslavia.

The American leader who had met with Stalin at Yalta, Franklin D. Roosevelt, died on April 12, 1945. The new American leader, Harry S. Truman, thought that Stalin not allowing free elections in Eastern European countries was clearly wrong. Truman, Stalin, and Churchill met in Potsdam, Germany, in July 1945. There, Truman asked Stalin to let the people in Eastern Europe have free elections. But Stalin refused. In a speech in early 1946, Stalin said that communism and capitalism (the economic system in the U.S.) could not exist peacefully in the same world.

An Iron Curtain Divides East and West

Europe was now divided into two sides: East and West. Germany had been split into two parts. The Soviet Union controlled the eastern part, including half of the city of Berlin. East Germany became a country called the German Democratic Republic, which had a Communist government. The western parts of Germany became the Federal Republic of Germany in 1949. Winston Churchill described this division of Europe by saying it was like an "iron curtain" that had come down across the continent.

This "iron curtain" line separated mostly democratic countries in Western Europe from Communist countries in Eastern Europe.

The United States Tries to Stop the Soviets

In 1946 and 1947, things between the U.S. and the Soviet Union kept getting worse. The United States was very worried about the Soviet Union's growing power in Eastern Europe and wanted to do something about it.

President Truman came up with a plan called containment. This plan was about stopping the Soviet Union from spreading its influence and preventing the spread of communism. To do this, the U.S. made alliances with other countries and helped weaker countries resist being taken over by the Soviets.

The Truman Doctrine

In a speech asking Congress for money to help Turkey and Greece, Truman explained the difference between democracy and communism. He said that democracy is based on what most people want, with free elections and no political oppression. Communism, on the other hand, is based on a small group forcing their will on everyone else, using fear and unfair elections. Truman said that the United States should support free people who are trying to resist being controlled by armed groups or outside pressure.

This idea of supporting countries that were against communism was called the Truman Doctrine. It caused a lot of debate. Some people didn't like the U.S. getting involved in other countries' problems. Others thought the U.S. couldn't afford to fight communism all over the world. But Congress quickly approved over $400 million in aid for Turkey and Greece.