Home Front, Internment and the Atomic Bomb: The Americas Transformed by War (History HL)

The Second World War changed daily life across the Americas. Millions of men left for the armed forces, so governments had to find new workers, new soldiers and new ways of organizing society. This section looks at how the war reshaped the roles of women and minorities, and how conscription — compulsory military service — brought new groups into the war effort.

Women in the wartime economy

In the United States, roughly 6 million women entered the paid workforce for the first time between 1941 and 1945, many in weapons and aircraft factories. The government used propaganda such as the "Rosie the Riveter" campaign to encourage this. Women also served in uniformed but non-combat roles, such as the Women's Army Corps (WAC) and the WAVES (Navy). In Canada, similar patterns emerged: the Canadian Women's Army Corps was created in 1941, and women filled factory jobs vacated by men.

Temporary or lasting change?: Most women were expected to leave their wartime jobs once men returned in 1945, and many did. But the war proved women could do industrial and military work, which fed into later arguments for equal rights — an important historiographical debate for essays on social change.

Minorities and the war effort

African Americans served in segregated units (such as the Tuskegee Airmen) and pushed for the "Double V" campaign — victory over fascism abroad and victory over racism at home. Mexican Americans also served in large numbers and worked in war industries, while the Bracero Program (1942) brought Mexican agricultural labourers into the US to replace workers who had joined the military. Indigenous peoples across the Americas, including many First Nations soldiers in Canada, also enlisted despite ongoing discrimination at home.

Conscription

The US introduced the Selective Training and Service Act (1940), its first peacetime draft, later expanded once the US entered the war in December 1941. Canada passed the National Resources Mobilization Act (1940) for home defence, but overseas conscription remained politically explosive — it triggered the 1944 Conscription Crisis, dividing English-speaking and French-speaking (Québécois) Canadians, many of whom opposed being sent to fight in Europe.

Link social change to the essay question: If asked about the social impact of the war, always name specific groups (women, African Americans, Mexican Americans, Québécois) and specific policies. Vague statements like "society changed a lot" score poorly at HL.

After the Japanese attack on Pearl Harbor (7 December 1941), fear and racism led governments across the Americas to target people of Japanese descent, even those who were citizens and had committed no crime.

United States

In February 1942, President Franklin D Roosevelt signed Executive Order 9066, authorizing the forced removal of around 120,000 Japanese Americans (two-thirds of them US citizens) from the West Coast into inland internment camps such as Manzanar. They lost homes, businesses and property, often sold at a fraction of their value. The Supreme Court upheld the policy in *Korematsu v United States* (1944), ruling that military necessity justified the exclusion — a decision widely criticized by historians today.

Canada

Canada interned around 22,000 Japanese Canadians, mostly from British Columbia, under the War Measures Act. Property was confiscated and sold without consent. Unlike in the US, some restrictions on Japanese Canadians (such as the right to vote) remained in place until 1949, four years after the war ended.

Latin America

Latin American governments cooperated with the US in a lesser-known policy: over 2,200 Japanese Latin Americans, mostly from Peru, were arrested and deported to US internment camps, partly to be used as hostages for prisoner exchanges with Japan. Many were left stateless after the war, unable to return to Peru or gain US citizenship.

Why this matters for essays: Internment shows a gap between the Allies' stated war aims (fighting for freedom and democracy) and their actual treatment of minorities at home. This tension is a strong analytical point for essays on wartime civil liberties or the limits of democracy.

Redress came decades later: The US formally apologized and paid reparations under the Civil Liberties Act (1988). Canada issued a formal apology and compensation in 1988 too. Note these dates are AFTER the syllabus period but useful as long-term consequence in an essay's final paragraph.

Reasons for the US use of atomic weapons

In August 1945, President Harry Truman ordered atomic bombs dropped on Hiroshima (6 August) and Nagasaki (9 August), developed through the Manhattan Project. Historians debate the reasons:

Significance

Japan surrendered on 15 August 1945 (formally signed 2 September), ending the Second World War. The bombings killed an estimated 200,000 people by the end of 1945 through blast, fire and radiation. They opened the nuclear age, shaping the Cold War arms race between the US and USSR, and remain one of the most debated moral questions in modern history.

Don't just describe — evaluate: A strong essay weighs these reasons against each other rather than listing them. Was military necessity the main driver, or was Cold War signalling more important? Reach a clear, supported judgement.

Economic effects: USA and Canada

The war ended the Great Depression in North America. Massive government spending on weapons, ships and aircraft ended unemployment: US industrial production roughly doubled between 1939 and 1945. The US emerged from the war as the world's dominant economic power, holding about half of global manufacturing output and gold reserves by 1945. Canada also industrialized rapidly, becoming the world's fourth-largest economy by 1945, with wartime production (the British Commonwealth Air Training Plan, munitions, and Victory Bonds) transforming its industrial base.

Diplomatic effects: USA and Canada

The war pulled the US away from isolationism permanently: it became a founding member of the United Nations (1945) and adopted a leading role in postwar international affairs, setting the stage for the Cold War. Canada also gained new diplomatic standing, joining the UN as a founding member and strengthening ties with both Britain and the US — a position historians call a "North Atlantic Triangle".