Paper 3

16. Why did the United States become involved in the Second World War?

Camilla Burkot
Intro/Background Info:

  • - Circumstances preceding the war suggested the US would not be involved in another international war for some time:
    • o Isolationism (1930s): after WWI, the US feared becoming involved in other countries’ affairs (remember, the US never joined the League of Nations)
      •  Key post-war peace treaties: the Washington Conference (1921-1922), the Kellogg-Briand Pact (1928)
      •  Domestically, the Neutrality Acts were passed by Roosevelt to pursue isolationism
        • • The first act (1935) banned the sale of arms to either belligerent in a war
        • • The second act banned loans to belligerents
      •  Isolation is also reflected in the policy of protectionism – high tariffs throughout the 1920s
    • o Great Depression (1929 to around 1940-1): financially, the country was still recovering (and much of the federal budget was invested in New Deal programs) and was not prepared to pay for a war
  • - Nevertheless, the US entered the World War II on December 7, 1941 (Pearl Harbor)

Thesis: While the attack on Pearl Harbor triggered the official entrance of the US into World War II, this was only the short term cause of US involvement. US preparation for and involvement in the war was largely due to Roosevelt’s foresight and actions in response to the situation developing in Europe throughout the 1930s. US commitment to protect democracy ultimately outweighed domestic calls for isolation.

A. Reversal of Neutrality Acts

  • a. Roosevelt, although he supported the Neutrality Acts, was concerned about events developing overseas by the late 1930s (rise of fascism, totalitarianism, etc.). Key events:
    • i. 1922: Establishment of USSR. Stalin ruler after 1924.
    • ii. 1922: Mussolini takes power in Italy
    • iii. 1931: Militarist Japan invades Manchuria (China)
    • iv. 1933: Hitler appointed Chancellor of Germany
    • v. 1936-39: Spanish Civil War. Franco becomes dictator
  • b. In light of these events, Roosevelt felt the US had a responsibility to protect peace and freedom: “The peace, freedom, and security of 90 percent of the population of the world is being jeopardized by the remaining 10 percent who are threatening a breakdown of all international order and law.” (1937).
    • i. Began a military buildup and increase in the military budget as a precaution.

*ii. Instituted the first peacetime draft, the Selective Training and Service Act, in 1940

  • c. By this point, isolationism was waning in the US, but many still did not want to become involved overseas – many Americans felt that the US entered WWI because of greedy arms dealers and banks which sold weapons to warring European nations
  • d. Roosevelt ultimately got around the Neutrality Acts when Japan invaded China again in 1937 by arguing that Japan never formally declared war on China, so the Neutrality Acts did not apply – therefore, arms and supplies could be sent to China.

B. “Cash-and-carry”

  • a. Two days after Hitler invaded Poland in 1939, Roosevelt assured Americans that he was committed to keeping the US neutral
  • b. Nevertheless, Roosevelt revised the Neutrality Act of 1935 (no sale of arms to belligerents), asking Congress to pass a Neutrality Act of 1939 which would permit warring nations to buy US arms as long as they paid cash and transported the weapons in their own ships.
    • i. Isolationists were infuriated by this proposition
    • ii. After 6 weeks of debate, the Act was passed
  • c. In 1940, the Tripartite Pact (mutual defense treaty) was signed between Japan, Germany, and Italy
    • i. Roosevelt recognized that, should war break out, the US would be forced to fight on two fronts (Atlantic and Pacific oceans)
    • ii. He saw Britain as the last defense between America and the Axis Powers
    • iii. To avoid a direct threat to the US, he sent Britain 500,000 rifles and 80,000 machine guns by June 1940 and in September traded 50 old US destroyers for leases on British military bases in the Caribbean and Newfoundland – an act which Winston Churchill called “decidedly unneutral”

C. “Lend-lease”

  • a. Shortly after reelection to his third term, Roosevelt began addressing the public about how Hitler could not be stopped through negotiation, and argued that the US had turn itself into “the great arsenal of democracy”
  • b. Because Britain had no money left to spend on US arms by late 1940, Roosevelt devised the lend-lease policy
    • i. Under the policy, the president would lend or lease arms or supplies to “any country whose defense was vital to that of the United States”
    • ii. Compared it to lending your garden hose to your neighbor whose house is on fire
  • c. Most Americans favored the Lend-Lease Act, and it was passed by Congress in March 1941
    • i. Britain and the USSR, which had by this point broken with Germany, received Lend-Lease aid

D. The Last Straw: Direct Attacks on the US and Final Preparations for War

  • a. From its aid to the Allies by 1941, it was pretty clear whose side the US was on
  • b. Hitler, in an effort to keep lend-lease aid from reaching Britain, ordered U-boat attacks on ships in the North Atlantic
    • i. At night, groups of up to 40 submarines (“wolf packs”) patrolled the north Atlantic Ocean
    • ii. These wolf packs were successful in sinking as many as 350,000 tons of supplies in a single month
    • iii. In June 1941, Roosevelt granted the US naval warships permission to attack the U-boats in self-defense
  • c. In August 1941, Roosevelt met secretly with British PM Winston Churchill on the USS Augusta to settle a joint declaration of war aims called the Atlantic Charter
    • i. Both the US and Britain pledged collective security, disarmament, self-determination, economic cooperation, and freedom of the seas
    • ii. Roosevelt confided in Churchill that he could not ask Congress to declare war, but that he would do everything to provoke an incident which would allow the US to enter the war on the side of the Allies
  • d. By autumn 1941, German U-boats were actively attacking US ships:
    • i. September 4: attack on USS Greer
    • ii. Mid-September: the Pink Star (merchant ship) is sunk
    • iii. Mid-October: USS Kearney is sunk, with 11 US casualties
    • iv. Days later: USS Reuben James is destroyed, with 100+ US casualties
      • 1. Roosevelt declared: “America has been attacked. The shooting has started. And history has recorded who fired the first shot.”
      • 2. Congress repealed the ban on arming merchant ships – the undeclared naval war with Germany had begun
  • e. Official war against the Axis began only with the attack on Pearl Harbor (December 7, 1941 – “a date which will live in infamy”)
    • i. Over 2000 US dead, 1000+ injured, nearly the entire US Pacific fleet destroyed along with 300 aircraft
    • ii. Congress quickly approved Roosevelt’s declaration of war on Japan
    • iii. Three days later, Germany and Italy declared war on the US
    • iv. Pearl Harbor was the final straw – many former isolationists expressed full support for the US war effort. Ex.: Senator Burton Wheeler: “The only thing to do now is to lick the hell out of them.”


  • Although public sentiment in the US strongly favored isolation from the war in Europe, Roosevelt saw where the war was headed and felt obligated to protect democracy
  • Who knows what might have happened, but it seems likely that Nazi Germany and the Axis would have eventually attacked the US as Japan did in 1941
  • One good outcome of the US entering WWII: ultimately, it achieved the goal of definitively ending the Great Depression as the economy mobilized for the war effort

I. Introduction
a. The Second World War started as a war between European nations and escalated into a conflict which spread around the globe. Although the war started September 1, 1939, the US did not enter the war until December 8, 1941. Some argue that the war could not have been won by the allies if it were not for American involvement. For this reason, it is important to investigate the reasons the United States entered the Second World War. The United States’ involvement in WWII cannot be attributed to a single cause; a number of factors played into the country’s decision to join the war. The first and the most obvious is that the Japanese directly attacked Pearl Harbor, a US naval base. However, the United States also had economic and political ties to Great Britain and did not want to see her defeated. Additionally, the Germans had been practicing unrestricted submarine warfare resulting in the sinking of American ships and the deaths of American soldiers.
II. Unrestricted Submarine Warfare
a. Germany was violating neutrality of the seas and attacking American ships carrying supplies to Britain
III. Pearl Harbor
a. US had put economic pressure on Japan because their drive to create economic empire clashed with Open Door Policy
i. July 1940—prohibits sale of gasoline to Japan
ii. Embargoes metals, chemicals, and machine parts to Japan
iii. When Japan takes over all of Indochina, July 1941, US cuts of all trade
b. December 7, 1941 – a surprise attack on Pearl Harbor kills 2,100 American soldiers
IV. Ties to Britain
a. The US had revised their Neutrality Acts to permit sale of weapons to belligerents on cash-and-carry basis in 1939
b. Churchill appealed to FDR for help in 1939
c. Lend-Lease Act of 1941
d. “Arsenal for Democracy” Churchill and FDR meet on battleship, issue Atlantic Charter outlining their wartime goals
V. Conclusion

Paper Three: Question 16: Why did the US become involved in WWII? (KELSEY MASE!!))

1) Introduction:
a) World War II broke out in Europe
b) Roosevelt was concerned as to what position to take in this war so he called all of his staff advisors together to discuss the position that America should take. It was decided that the United States would remain neutral in the matter.
c) America was not yet directly at risk
d) Neutrality Act – 1935
e) US may not have been prepared to fight
2) Distant reasons for involvement
a) Outside of the US
i) Expansionist designs of totalitarian regimes in Japan, Italy, and Germany.
ii) In 1931 Japan had invaded Manchuria, crushed Chinese resistance, and set up the puppet state of Manchukuo.
iii) Italy, under Benito Mussolini, enlarged its boundaries in Libya and in 1935 conquered Ethiopia.
iv) Germany, under Nazi leader Adolf Hitler, militarized its economy and reoccupied the Rhineland (demilitarized by the Treaty of Versailles) in 1936. In 1938, Hitler incorporated Austria into the German Reich and demanded cession of the German-speaking Sudetenland from Czechoslovakia.
b) Directly related to the US
i) Disillusionment from WWI
ii) The objective was to prevent, at almost any cost, the involvement of the United States in a foreign war.
iii) At the outbreak of World War II, isolationist sentiment increased, even though Americans clearly favored the victims of Hitler's aggression and supported the Allied democracies, Britain and France.
iv) Roosevelt could only wait until public opinion regarding U.S. involvement was altered by events.
3) Immediate causes of US involvement
a) In early 1941, Roosevelt got Congress to approve the Lend-Lease Program, which enabled him to transfer arms and equipment to any nation (notably Great Britain, later the Soviet Union and China)
b) In August, Roosevelt met with Prime Minister Churchill off the coast of Newfoundland. The two leaders issued a "joint statement of war aims," called the Atlantic Charter.
d) the Japanese attacked Pearl Harbor on December the 6 th, 1941
i) American opinion, still divided about the war in Europe, was unified overnight by what President Roosevelt called "a day that will live in infamy." On December 8, Congress declared a state of war with Japan; three days later Germany and Italy declared war on the United States.

Eli Hungerford
16. Why did the United States become involved in the Second World War?

I. Introduction
The United States attempted to remain neutral and isolationist during the Second World War, but the fact that they were selling arms and supplies to the allies caused conflict with Germany and the axis powers. The United States had many reasons to become involved in WWII, such as Germany’s violation of neutrality of the seas and economic ties to the allies. However, the tipping point came when the Japanese attacked Pearl Harbor without any warning that hostilities were taking place and without a declaration of war.
II. Ties to Allied nations
A. Traded greatly with Britain, France and Russia, causing the US to view them more favorably than the Axis powers.
B. Neutrality Act of 1939
1. Permitted the US to legally sell arms to belligerent nations
C. Lend lease act
1. Permitted the US to lend arms or assistance to nations whose defense was vital to the United States.
2. Needed because Britain had run out of money to purchase weapons and supplies under the Neutrality act of 1939.
III. Germany’s violation of neutrality of the seas
A. Germany, in an attempt to prevent supplies from reaching the Allies permitted its U-boats to attack ships in the Atlantic
B. Merchant ships were sunk.
C. Roosevelt met with Churchill to discuss the terms of the US declaring war.
IV. Attack on Pearl Harbor
A. Japanese planes bombed US naval base Pearl Harbor with no warning of the beginning of hostilities.
1. This took out most of the battle fleet and caused many casualties.
2. “A date which will live in infamy”
3. Public outcry for war
B. Roosevelt asks Congress to declare war on Japan and everyone except 1 person passed it.
C. Germany declares war on the US and Roosevelt reciprocates.
V. Conclusion

Paper 3
16. Why did the United States become involved in the Second World War?
Alisha Virani

-began on September 1, 1939
-a war between European nations
-US entered on December 8, 1941

Reasons for US involvement:
-Japan attacked a US naval base, Pearl Harbor
-December 7, 1941 Japan was angered by the US’s attempts to overthrow the Open Door Policy
-2, 100 American soldiers died
-Allied with Great Britain
-Churchill requested help from FDR
-Lend Lease Act of 1941
-Submarine warfare with Germany
-lead to the sinking of American ships carrying supplies
-death of Americans

Conclusion: The US was justified in joining the war and this also proved to be beneficial to its allies.

Emma Bogdan 16. Why did the United States become involved in the Second World War?

• US wanted to stay neutral and isolate from the conflicts that were arising among the other nations – however, by sending military supplies the US president was contradicting himself and fighting a war he promised he would not.
• Isolationism – Neutrality Act of 1939 – ensured that the US would not get involved again in foreign conflict, esp. in Europe
• The United States officially entered WWII on December 8, 1941 – even though America was not prepared for war
• US declared war on Japan following the Japanese attack on Pearl Harbor
• Nazi Germany sunk American ships carrying supplies to the Allied troops (England, China, Russia and France)
• before the war, the U.S. economy was still not fully recovered from the Great Depression – but FDR mobilized it quickly

I. Rise of Totalitarian Regimes was a concern
- 1933 – Hitler becomes leader in Germany – rise of Nazi fascism
- purpose of protecting democracy & protecting US interests– Hitler was taking over all Europe and isolationism
- 1939 – after Germany invaded Poland, US was still determined to remain neutral
- Britain and USSR receive Lend Lease support from the United States, which allowed the US to send supplies and arms to any country crucial in protecting the US
- Hitler ordered an U-2 attack on US cargo ships to stop them from reaching their destinations – Britain – by 1941 Germans were attacking US ships

II. Conflict with Japan and ties to Britain
- The aftereffects of Pearl Harbor – over 2000 US dead, 1000+ injured, US aircrafts and almost whole pacific coast fleet destroyed
- Japan had been hostile towards China – United States cut trade with Japan in 1940 – oil embargo
- US declares war on Japan, then Germany & Italy declare war on US
- to avoid fighting on two fronts, US relied greatly on Britain – sent 500,000 rifles and 80,000 machine guns by June 1940 and in September traded 50 old US destroyers for leases on British military bases in the Caribbean and Newfoundland
- Under the Lend-Lease policy, the US was able to send Britain supplies, without seeming to take sides
- August 1941, Roosevelt met secretly with Winston Churchill to settle a declaration of war aims called the Atlantic Charter
- United states and Britain pledged collective security, disarmament, self-determination, economic cooperation, and freedom of the seas
Conclusion: Even though the attack on Pearl Harbor was the ultimate cause for the United States’ involvement in WWII, along with the German threat, the United States also had further interests when entered the war – of protecting democracy and stopping the spread of the totalitarian regimes, and of protecting American economy and investments around the world.

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