In 1945, the United States was a far different country than it subsequently became. Nearly a third of Americans lived in poverty. A third of the country’s homes had no running water, two-fifths lacked flushing toilets, and three-fifths lacked central heating. More than half of the nation’s farm dwellings had no electricity. Most African Americans still lived in the South, where racial segregation in schools and public accommodations were still the law. The number of immigrants was small as a result of immigration quotas enacted during the 1920s.

After World War II, the United States clashed with the Soviet Union over such issues as the Soviet dominance over Eastern Europe, control of atomic weapons, and the Soviet blockade of Berlin. The establishment of a Communist government in China in 1949 and the North Korean invasion of South Korea in 1950 helped transform the Cold War into a global conflict.