President Roosevelt's New Deal laws, started back in the 1930s, changed America, creating strong child labor regulations, minimum wage standards, Social Security, and new taxes. Over the years the gap between rich and poor has narrowed. But some Americans don't like those New Deal ideas; they say they are communistic. Now Harry Truman wants to change society even more, with a program of liberal reform called the Fair Deal. To J. Edgar Hoover, head of the Federal Bureau of Investigation, it sounds like Communism. And fear of Communism is terrifying many Americans . Hoover says, "There are half a million fellow travelers and sympathizers in America ready to do the Communist bidding."

Then some Communist spies are discovered. They have sold atom-bomb secrets to Russia. And shocking news comes from England —some top British intelligence officials turn out to be Soviet spies. In 1949, Russia tests an atom bomb. The United States thought it had been alone in having atomic weapons. Now the idea that Joseph Stalin, a cold-blooded tyrant, has the A-bomb terrifies Americans .

In that same year, Communists take over China. Then North Korea, encouraged by communist China, sends an army into South Korea . Truman, working with the United Nations, decides to stop them. Though war is never declared, it becomes known as the Korean War. The Cold War has turned hot. Americans have become fearful that Communism will dominate the world. And because of those fears, we do some foolish things at home .