How did the United States move from isolationism to total war, and how did World War II transform the nation at home and in the world?
Topics 7.12 to 7.14 World War II, Mobilization, Military, and Home Front: the path from isolationism to war, total mobilization, the military effort, and the war's effects on American society.
A focused answer to AP US History Topics 7.12 to 7.14, covering World War II: the move from isolationism to war after Pearl Harbor, total economic and social mobilization, the home front including Japanese American internment and new roles for women and minorities, and the war's end and the atomic bomb.
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What this topic is asking
Topics 7.12 to 7.14 ask you to explain the Second World War for the United States: the move from isolationism to war after Pearl Harbor, the total mobilization of the economy and society, the military effort, and the war's effects on the home front, including Japanese American internment and new roles for women and minorities. The exam wants why the nation entered, how the war transformed society, and how it ended.
From isolationism to war
Total mobilization and the end of the Depression
The war required total mobilization, and that mobilization finally ended the Great Depression. Massive government spending and war production created full employment, and the United States became the "arsenal of democracy", out-producing all its enemies. The federal government grew enormously, directing the economy, rationing goods, and financing the war through taxes and war bonds. The wartime boom, far more than the New Deal, restored prosperity, demonstrating the power of government spending and setting the stage for postwar economic growth.
The home front
The end of the war
The United States and its allies fought a two-front war, defeating Germany in Europe by May 1945 and then turning fully against Japan in the Pacific. To force Japan's surrender and avoid a costly invasion, President Truman ordered the use of the new atomic bomb, destroying Hiroshima and Nagasaki in August 1945; Japan surrendered. The war left the United States the world's dominant economic and military power, its homeland untouched and its industry supreme, and the only nation possessing nuclear weapons. This unmatched power, and the rivalry with the Soviet Union that emerged from the wartime alliance, would define the Cold War of Period 8.
Worked example: arguing the war transformed society
Try this
Q1. Name the event of December 7, 1941, that brought the United States into World War II. [Recall]
- Cue. The Japanese attack on Pearl Harbor.
Q2. Explain how World War II changed the position of the United States in the world. [Short explanation]
- Cue. The war left the United States with its industry intact and vastly expanded while its rivals were devastated, so it emerged as the world's dominant economic and military power and the only nation with the atomic bomb; this unmatched strength, and the new rivalry with the Soviet Union, set the stage for American global leadership in the Cold War.
Exam-style practice questions
Practice questions written in the style of College Board exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
AP USH (style)3 marksBriefly describe ONE reason the United States entered World War II. Briefly explain ONE effect of the war on the American home front. Briefly explain ONE way the war changed America's role in the world.Show worked answer →
A Short Answer Question (SAQ), 3 points, one per bullet.
A. Describe: the Japanese attack on Pearl Harbor on December 7, 1941, ended isolationism and brought the United States into the war.
B. Home front: total mobilization ended the Depression, drew women and minorities into war work, and led to the internment of Japanese Americans.
C. Role in the world: the United States emerged from the war as the dominant economic and military power, and the only one with the atomic bomb.
Markers want a real cause, a concrete home-front effect, and a genuine change in America's global role.
AP USH (style)6 marksEvaluate the extent to which World War II transformed American society in the period 1941 to 1945.Show worked answer →
A Long Essay Question (LEQ), scored on the 6-point rubric.
Thesis (1): "World War II transformed American society profoundly, ending the Depression, expanding federal power, opening new roles for women and minorities, and raising the nation to superpower status, though it also produced injustices such as Japanese American internment."
Contextualization (1): the isolationism of the 1930s and the rise of aggressive dictatorships abroad.
Evidence (2): total mobilization and the changing roles of women and minorities; Japanese American internment and the atomic bomb.
Analysis (2): explain HOW the war remade the economy, society, and foreign policy, then add complexity by weighing the war's injustices and continuities in inequality.
Related dot points
- Topics 7.9 and 7.10 The Great Depression and the New Deal: the causes and effects of the economic collapse and the New Deal's expansion of federal power in response.
A focused answer to AP US History Topics 7.9 and 7.10, covering the Great Depression and the New Deal: the causes of the 1929 crash and the Depression, its human cost, Franklin Roosevelt's New Deal programs of relief, recovery, and reform, and how the New Deal permanently enlarged the federal government.
- Topics 7.5 and 7.6 World War I, Military, Diplomatic, and Home Front: the reasons for United States entry, the war effort, the fight over the peace, and the war's effects on American society.
A focused answer to AP US History Topics 7.5 and 7.6, covering the First World War: the reasons for United States entry from neutrality to 1917, the home front and the curbing of civil liberties, the Great Migration, Wilson's Fourteen Points, and the Senate's rejection of the Treaty of Versailles.
- Topic 7.1 Contextualizing Period 7: the reform, economic, technological, and global forces that made the United States a modern industrial world power between 1890 and 1945.
Sets the scene for AP US History Period 7, covering Progressive reform, overseas expansion, the two world wars, the boom and bust of the 1920s and 1930s, the New Deal, and how to write contextualization for a DBQ or LEQ on the emergence of modern America.
- Topic 7.15 Comparison in Period 7: using the historical reasoning skill of comparison to analyze the developments of the emergence of modern America.
A focused answer to AP US History Topic 7.15, teaching the historical reasoning skill of comparison through Period 7: comparing Progressivism and the New Deal, the two world wars, and the 1920s and 1930s, and how to frame a comparison essay for the DBQ or LEQ.
- Topics 7.7 and 7.8 The 1920s, Innovations and Cultural Conflict: the consumer and mass culture of the decade and the cultural and political controversies it provoked.
A focused answer to AP US History Topics 7.7 and 7.8, covering the 1920s: the consumer boom and mass culture of radio, film, and the automobile, the Harlem Renaissance, and the cultural conflicts over immigration, prohibition, religion, and race, from the Red Scare and the Scopes Trial to the revived Ku Klux Klan.
Sources & how we know this
- AP United States History Course and Exam Description — College Board (2020)