World War II was fought over differences left unresolved after World War I. Over 400,000 Americans perished in the four years of involvement, an American death rate second only to the Civil War. Twelve million victims perished from Nazi atrocities in the Holocaust. The deaths of twenty million Russians created a defensive Soviet mindset that spilled into the postwar era. After all the blood and sacrifice, the Axis powers were defeated, but the Grand Alliance that emerged victorious did not last long. Soon the world was involved in a 45-year struggle that claimed millions of additional lives — the Cold War.

Japan had an advance pledge of support from Hitler in the event of war with the United States. Now President Roosevelt faced a two-ocean war — a true world war. Despite widespread cries for revenge against Japan, the first major decision made by the President was to concentrate on Germany first. The American Pacific Fleet would do its best to contain Japanese expansion, while emphasis was placed on confronting Hitler's troops.

The large population, generous natural resources, advanced infrastructure, and solid capital base were all just potential. Centralization and mobilization were necessary to jump-start this unwieldy machine. Within a week of Pearl Harbor, Congress passed the War Powers Act, granting wide authority to the President to conduct the war effort. Throughout the war hundreds more alphabet agencies were created to manage the American homefront.

The time had finally come. British and American troops had liberated North Africa and pressed on into Italy. Soviet troops had turned the tide at Stalingrad and were slowly reclaiming their territory. The English Channel was virtually free of Nazi submarines, and American and British planes were bombing German industrial centers around the clock.

Pearl Harbor was only the beginning of Japanese assaults on American holdings in the Pacific. Two days after attacking Pearl Harbor, they seized Guam, and two weeks after that they captured Wake Island. Before 1941 came to a close, the Philippines came under attack. Led by General Douglas MacArthur, the Americans were confident they could hold the islands. A fierce Japanese strike proved otherwise.

Many Americans worried that citizens of Japanese ancestry would act as spies or saboteurs for the Japanese government. Fear — not evidence — drove the U.S. to place over 127,000 Japanese-Americans in concentration camps for the duration of WWII.

Early in 1939, the world's scientific community discovered that German physicists had learned the secrets of splitting a uranium atom. Fears soon spread over the possibility of Nazi scientists utilizing that energy to produce a bomb capable of unspeakable destruction. The Allies had to beat the Nazis to the punch.

When Harry Truman learned of the success of the Manhattan Project, he knew he was faced with a decision of unprecedented gravity. The capacity to end the war with Japan was in his hands, but it would involve unleashing the most terrible weapon ever known.

After the end of World War II, no single foreign policy issue mattered more to the United States for the next 50 years as much as the Cold War. President Truman set the direction for the next eight presidents with the announcement of the containment policy. Crises in Berlin, China, and Korea forced Truman to back his words with actions. The Cold War kept defense industries humming and ultimately proved the limits of American power in Vietnam. Democracy was tested with outbreaks of Communist witch hunts.

In 1945, one major war ended and another began. The Cold War lasted about 45 years. There were no direct military campaigns between the two main antagonists, the United States and the Soviet Union. Yet billions of dollars and millions of lives were lost in the fight.

Despite the ideological animosity spawned by the Cold War, a new spirit of globalism was born after WWII. It was based, in part, on the widespread recognition of the failures of isolationism. The incarnation of this global sprit came to life with the establishment of the United Nations in 1945 with its headquarters in New York City.

Communism was on the march. A mid-level diplomat in the State Department named George Kennan proposed the policy of containment. Since the American people were weary from war and had no desire to send United States troops into Eastern Europe, rolling back the gains of the Red Army would have been impossible. But in places where communism threatened to expand, American aid might prevent a takeover. By vigorously pursuing this policy, the United States might be able to contain communism within its current borders.

Berlin, Germany's wartime capital was the prickliest of all issues that separated the United States and Soviet Union during the late 1940s. The city was divided into four zones of occupation like the rest of Germany. However, the entire city lay within the Soviet zone of occupation. Once the nation of East Germany was established, the Allied sections of the capital known as West Berlin became an island of democracy and capitalism behind the Iron Curtain.

Containment had not gone so well in Asia. When the Soviet Union entered the war against Japan, they sent troops into Japanese-occupied Korea. As American troops established a presence in the southern part of the Korean peninsula, the Soviets began cutting roads and communications at the 38th parallel. Two separate governments were emerging, as Korea began to resemble the divided Germany.

The end of World War II brought a series of challenges to Harry Truman. The entire economy had to be converted from a wartime economy to a consumer economy. Strikes that had been delayed during the war erupted with a frenzy across America. Inflation threatened as millions of Americans planned to spend wealth they had not enjoyed since 1929. As the soldiers returned home, they wanted their old jobs back, creating a huge labor surplus. Truman, distracted by new threats overseas, was faced with additional crises at home.

A booming economy helped shape the blissful retrospective view of the 1950s. A rebuilding Europe was hungry for American goods, fueling the consumer-oriented sector of the American economy. Conveniences that had been toys for the upper classes such as fancy refrigerators, range-top ovens, convertible automobiles, and televisions became middle-class staples.

Senator Joseph McCarthy rose to national prominence by initiating a probe to ferret out communists holding prominent positions. During his investigations, safeguards promised by the Constitution were trampled.

Racial fears, affordable housing, and the desire to leave decaying cities were all factors that prompted many white Americans to flee to suburbia. And no individual promoted suburban growth more than William Levitt.

Perhaps no phenomenon shaped American life in the 1950s more than television. At the end of World War II, the television was a toy for only a few thousand wealthy Americans. Just 10 years later, nearly two-thirds of American households had a television.

This generation of youth was much larger than any in recent memory, and the prosperity of the era gave them money to spend on records and phonographs. By the end of the decade, the phenomenon of rock and roll helped define the difference between youth and adulthood. Rock and roll sent shockwaves across America. A generation of young teenagers collectively rebelled against the music their parents loved. In general, the older generation loathed rock and roll. Appalled by the new styles of dance the movement evoked, churches proclaimed it Satan's music.