The extent of change in the domestic United States during the Second World War from 1939 to 1945 can be measured via production, internment camps, racism, and opportunities for women.

In terms of production, the Second World War changed what America could produce. To battle Nazi Germany and its allies, the United States began making weapons. Before the war, the United States made very few weapons. During the war, America began producing more weapons than its enemies. Not only was the United States manufacturing a high quantity of weapons, but it was creating technologically advanced weapons. Aside from weapons, Americans at home were producing critical drugs like penicillin and materials like plastic—the latter as a substitute for rationed metals.

For Japanese people living on the West Coast, things changed for the worse during World War II. Worried that they might be colluding with Japan, a World War II opponent, the American government forcefully removed them and held them in internment camps. Black people continued to confront racism during World War II, although President Franklin D. Roosevelt forbade discrimination in the defense business. The lives of women in America changed dramatically, with more than six million women finding jobs during the war. Indeed, at one point in World War II, working married women outnumbered working single women.