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The U.S. Enters WWI

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British Naval Blockade

  • 1914
  • Great Britain blocks all ships headed to Germany (even neutral ones).
    • Creates a “blockade”.
  • The block makes trade with Germany difficult & pushes the U.S. to war.

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German U-Boats

  • February 1915: U-boats (submarines) were used to break the blockade.
  • Germany claimed they could sink any enemy ships around Great Britain.
  • U.S. ships were at risk:
    • British ships often flew the U.S. flag to avoid being attacked.
    • This pushes the U.S. closer to war.

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Lusitania

  • May 1915: U-boat sank the British liner, Lusitania, without warning.
    • Killing about 1,200 people & 128 Americans.
  • Germans said the ship was carrying weapons & ammunition.
  • Roosevelt: “Murder on the high seas”
  • This act makes neutrality difficult for the U.S. & pushes them towards war.

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The Sussex Pledge

  • August of 1915: German U-boats sank two more British ships.
    • Kills 2 Americans & injures several.
  • Sussex Pledge: Germany promised not to kill any more people in U-Boat attacks if US promised to make Britain stop their blockade.
  • Wilson did not accept this condition.
  • This offer insultes Wilson & the U.S. tensions with Germany get worse, pushing them towards war.

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Preparedness Movement

  • Summer of 1916: The U.S. starts to prepare for war.
  • Wilson raises the money to:
    • Grow the army from 80,000 to 1 million
    • Build a bigger navy than even Great Britain’s.
  • This militarism shows the U.S. is really considering war now.
    • Germany knows it.

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Propaganda & the Bryce Report

  • Propaganda: Information spread by a group to promote a cause or to damage an opposing cause or idea.
  • 1916: Historian Lord Bryce led the British propaganda machine that wanted to make the Germans look evil.
  • Known as the Bryce Report, these stories increased anti-German feelings in the U.S., pushing them towards war.

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Unrestricted German Submarine Warfare

  • February 1917: Germany returned to unrestricted submarine warfare.
    • No limits! No rules!
  • Germany wanted to crush the British & French before the U.S. entered the war.
  • The U.S. is angered.
    • Isolationism: They cut of all communication with Germany.
    • Start arming non military ships.

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Zimmermann Note

  • March 1917: German foreign minister, Arthur Zimmermann, sent a note to the German minister in Mexico.
  • It said that Mexico should start a war against the US if the great power entered WWI.
    • Mexico would get TX, AZ & NM.
  • The note is found by the British who publish it.
  • The U.S. has been directly threatened - they are very close to war!

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Russian Revolution

  • Czar Nicholas II is overthrown in the Bolshevik Revolution of 1917.
    • An autocratic ruler is removed.
    • A single person with total power.
  • Wilson didn’t want to be allied with such a ruler.
    • Now, he can ally himself with a country that has a chance for democracy.
  • The U.S. has nothing standing in its way - war is about to start for the U.S.

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U.S. Declares War

This would be the final straw:

US will declare war on Germany on April 4, 1917.