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FDR and World War II

After leading the United States through nearly a decade of Depression, President Franklin Delano Roosevelt took on the role of Commander-in-Chief when the United States entered the Second World War. 


  • Democrat Franklin Delano Roosevelt led the nation through the Second World War.
  • Roosevelt built a powerful wartime coalition with Britain and the Soviet Union, and led the nation to victory against Nazi Germany.
  • His wartime efforts prepared the path for his successor, Harry Truman, to win the war against Japan four months after his death.
  • He was elected to the presidency four times, serving from March 1933 until his death in office in April 1945.

Foreign policy in the 1930s

The worldwide economic depression of the 1930s took its toll in different ways in Europe, America, and Asia. In Europe, political power shifted to totalitarian and imperialist governments in several countries, including Germany, Italy, and Spain. In Asia, a resource-starved Japan began to expand aggressively, invading China and maneuvering to control a sphere of influence in the Pacific. The United States, on the other hand, chose to withdraw from world affairs and concentrate on its own economic problems.
During the Great Depression, Americans were in favor of isolationism, believing that problems at home could only be exacerbated by engagement in international affairs. Thus, President Franklin Delano Roosevelt's engagement in foreign affairs was limited, even as the gathering storm of Japanese and German military aggression dimmed global prospects for peace.
Photograph of two British soldiers taking guns out of crates.
British soldiers receive a shipment of American weapons provided by the Lend-Lease Act. Image courtesy the Imperial War Museum.
Even after war broke out in Europe following Hitler's invasion of Poland in 1939, Roosevelt, reflecting national sentiment, maintained US neutrality. Indirectly, however, Roosevelt supported the British and the Allies in their fight against Nazi Germany. In 1942, Roosevelt made a speech declaring that the United States would serve as an “arsenal of democracy” for the Allies by supplying them with American-made weapons and equipment through the Lend-Lease program.start superscript, 1, end superscript

Roosevelt as Commander-in-Chief

US neutrality in World War II ended after the Japanese (who were allied with Nazi Germany) launched a surprise attack on Hawai'i's Pearl Harbor. Rousing the nation in a national radio address the following day, President Roosevelt declared the date of that attack, December 7, 1941, a “date which will live in infamy.”squared
Franklin Roosevelt meeting with General MacArthur, Admiral Leahy, and Admiral Nimitz in 1944. Image courtesy Wikimedia Commons.
For the United States, the Second World War was simultaneously fought in two theaters of military combat, in Europe and in the Pacific, a war involving sixteen million American men mobilized into the armed forces—405,000 of whom lost their lives.cubed
Article II, Section 2 of the Constitution provides that, "The president shall be Commander-in-Chief of the Army and Navy of the United States.” In keeping with this Constitutional grant of authority, Roosevelt led the nation in war. He built a close partnership with British Prime Minister Winston Churchill, and later with Soviet premier Joseph Stalin in the fight against Nazi Germany. True to his word, the United States did become the arsenal of democracy, supplying some $50 billion in desperately needed weapons and equipment to the British, Soviets, and other Allied Forces during the war.start superscript, 4, end superscript

The 'Four Freedoms'

During the interwar years and in the war itself, a great worldwide battle of values, forms of government, and economic systems was underway, pitting liberal democracy against fascism, Nazism, and communism. Roosevelt’s advocacy of American ideals and institutions gave eloquent expression to the tenets of liberal democracy for which the nation fought, and included stirring public statements of the importance of America’s founding principles of representative government, religious freedom, toleration, individual liberty, free speech, and capitalism.start superscript, 5, end superscript
In his January 1941 State of the Union Address—often called the Four Freedoms speech—Roosevelt cast the war as a fight for four universal human freedoms, freedom of speech, freedom of religion, freedom from want, and freedom from fear.
Roosevelt's expressions of the core values of a free and open society inspired many in the United States and around the world, even though he did not always live up to those principles. Roosevelt succumbed to fear and racism when he issued Executive Order 9066, which interned 112,000 Japanese Americans during the war.

Roosevelt's death and legacy

Roosevelt was in poor health in the later years of his presidency. The combined toll of his struggle with polio and his role as Commander-in-Chief wore him down. On April 12, 1945 Roosevelt died from a cerebral hemorrhage while visiting Georgia. His vice president, Harry S. Truman, took over the presidency. It fell to Truman to see the United States to final victory in World War II.start superscript, 6, end superscript
Nevertheless, Roosevelt is often ranked, along with Washington and Lincoln, as among the nation’s greatest presidents. His wife, Eleanor, was famous in her own right for transforming the position of First Lady into an office of advocacy and activism during his presidency.

What do you think?

Do you agree with historians who rate Franklin Roosevelt one of the greatest presidents in US history? Why or why not?
Could President Roosevelt have done more to stop the coming of the Second World War? If so, what might he have done?
Do you think Roosevelt was a good wartime leader? Why or why not?

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