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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.
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.1

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.”2
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.3
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.4

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.5
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.6
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?

Want to join the conversation?

  • primosaur ultimate style avatar for user NoahRehberg
    Why did Japan join the allies in world war 1 but the Nazis in world war 2?
    (21 votes)
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    • duskpin ultimate style avatar for user StarBoy4
      Because the allies were mostly against the push japan was taking. Japan was a small nation lacking in "elbow space", so they seeked more land and invaded china. Since the Germans were more friendly, they joined the axis. They joined the allies in ww1 because they wanted to be acknowledged as a world power. Their invasion of Germans in africa proved military might.
      (22 votes)
  • blobby green style avatar for user amuschel
    why was hitler against jews
    (6 votes)
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    • aqualine tree style avatar for user David Alexander
      1) Hitler was a poor man of his times.
      2) Hitler was also a man with a tremendous ambition to be in power.
      3) When he looked at the political possibilities to attain that power, he concluded that rising by hatred was a pretty safe bet.
      4) In Middle Europe, there was already a strong anti-jewish sentiment among some sectors of gthe society. This sentiment went back centuries. It was wrong, it was terrible, but it was there. Hitler made use of that anti-jewish sentiment on his way up the political ladder.
      5) Jewish people, as individuals, as a distinct ethinic group, and as a religious group, had done nothing at all to "earn" the hatred of others.
      6) My own conclusion is that Hitler was a very bad man who rose to power by exploiting class and race hatred in a people (the ethnic Germans) at a time when they were feeling down and oppressed. I emphasize that Hitler was a very bad man. Those who blindly followed him shared in his badness.
      (10 votes)
  • winston baby style avatar for user ds35058
    Why did they attack Pearl Harbor?
    (3 votes)
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  • male robot johnny style avatar for user SJ MW
    why was Hitler against people that were Jewish?
    (2 votes)
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    • female robot ada style avatar for user AJ Jones❤️
      Theory of Superior Race.
      One of the most important reasons for Hitler’s deep seated aversion for the Jews was that he thought of them as an inferior race. In his speeches and conversations, Hitler passionately stated his belief that the Germans were the descendants of the mighty Aryan race.
      (12 votes)
  • blobby green style avatar for user chhuon.menglin
    In my point of view, I agree with the historians who rated FDR one of the greatest presidents in US history to a greater extent. In sooth, he did not pay lip service, taking action here and there to help the American nation. Simply put, he was a great president in terms of his presidency. When The Japanese launched a surprise attack on the US navy base, he spontaneously responded to the attack by proposing his idea to the constitution to grant the right to encounter the ferocious attack.
    (4 votes)
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    • leafers tree style avatar for user L. E.
      I agree, for the most part. FDR was certainly a strong president who represented America well during the war. However, I believe many of the socialist-leaning welfare policies he implemented in the '30s have helped form our economic problems today.
      (1 vote)
  • blobby green style avatar for user NayeliH
    why was hitler against jews
    (2 votes)
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    • aqualine tree style avatar for user David Alexander
      He was hateful and hate-filled. The Jews were the convenient target. Had he been in China instead of Europe, he would have found some group there to blame. This happens all over the world. Someone hateful and hate-filled finds someone else to blame for his or her troubles.
      (7 votes)
  • blobby green style avatar for user 33077
    why does the us always help other countrys when they are in fights?
    (2 votes)
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  • blobby green style avatar for user schlaff, steven
    Why did they need big shipments of guns for the war
    (2 votes)
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  • male robot hal style avatar for user Zev Oster
    Do you think Hitler hated the Jews, or did he want power for his own sake? Discrimination of Jews as a political maneuver has been common for almost as long as Judaism has existed, and almost all of the old world has harbored such a nation at one point or another, including in Palestine itself.
    (3 votes)
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    • duskpin ultimate style avatar for user Ethan M
      Most likely it was a mix of both. Through out his childhood he had bad experiences with those who were Jewish and learned to hate them. However it is definitely possible part of the fuel was his thirst for power, and his thirst to destroy all who weren't a part of his "Aryan" race.
      (3 votes)
  • duskpin seedling style avatar for user Ashley
    i think he could have been a better leader, he may have stopped some of the chaos that was going on, but he also cause some, why didn't he try harder to prevent WW2?
    (2 votes)
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