Despite the forced repatriations of 100,000 Mexicans and Mexican Americans during the Depression, the United States reached out to its neighbors in Latin America, adopting the Good Neighbor Policy in 1933. This policy stepped back from the heavy-handed and aggressive policies that the US had pursued in the region previously; the US committed to not interfering in Latin American affairs. US media also portrayed Latin American culture in a positive light.

However, the Good Neighbor Policy suffered a setback when the Mexican government created PEMEX, nationalizing its oil resources. Eventually, a settlement was reached. Mexico agreed to pay for the value of the oil that it had nationalized. The invasion of Poland (September 1st, 1939) followed by declarations of war by France and Britain on September 3rd immediately involved Canada in the war; the Canadian declaration of war came on September 10th, 1939.

Canadian aircraft participated in the Battle of Britain, and transatlantic convoys supplied Britain with soldiers, food, weapons, and other necessary equipment. Escorted by the Canadian navy, the convoys nonetheless suffered terrible losses during the crucial Battle of the Atlantic. Over a million Canadians took part in the war; 42,000 Canadians lost their lives.

The United States, committed to its neutrality, supported Britain, adding the “cash and carry” policy to the 1939 Neutrality Act, allowing US businesses to sell weapons to Allied nations on a “cash and carry” basis. The Lend-Lease Act (1941) expanded on this policy. Japan’s invasion of French Indochina led to a US embargo on shipments of oil to Japan.

The Japanese could not sustain their war-effort without this oil, and decided to expand the war in the Pacific, attacking Pearl Harbor on December 7, 1941. This “day that will live in infamy” prompted the US entry into the war on December 8th. By February, Roosevelt had signed an order for the internment of the Japanese Americans in the United States and the creation of a vast exclusion zone along the west coast of the United States. For the remainder of the war, most Japanese Americans were imprisoned in internment camps. However, some enlisted and fought in US forces.

In Canada, a similar fear of citizens of Japanese ancestry prompted the establishment of Canadian internment camps. Furthermore, an exclusion zone was created along the coast of British Columbia. Brazil and Peru, each with a substantial population of Japanese ancestry, arrested thousands of Japanese and deported some of them. Brazil also shut down Japanese schools, newspapers, and businesses.

The strategy of island hopping at last brought the US to the shore of Japan. Even after VE Day (May 8, 1945), the Japanese had continued to fight on. The United States had developed atomic weapons; fearing up to half a million casualties if a D-Day style assault was conducted against Japan, the US dropped two nuclear bombs, the first on Hiroshima (August 6, 1945), the second on Nagasaki (August 9, 1945). Over 200,000 civilian casualties were incurred. On August 15th, Japan surrendered.

The war had had an enormous impact on the United States. Women had gone to work in the armed forces and in the factories in record numbers. Images like “Rosie the Riveter” celebrated their contribution to the war effort. African Americans had served, once again in segregated units. After the war was over, President Truman integrated the military. The US economy boomed; US industrial output was the envy of the world. Soldiers returned, received college educations through the GI Bill, and bought houses in the suburbs that mushroomed across the country. And, the baby boom created millions of new families. After the War, Canada, like the US, experienced a baby boom. Its economy prospered through the 1940s and 1950s.