Causes
• Humanitarian Concerns
• Yellow Journalism
– Joseph Pulitzer
– William Randolph Hearst
• Protect U.S. economic interest in Cuba
• De Lôme Letter called McKinley “weak”
• Sinking of the U.S.S. Maine
Results
• U.S. get Philippines, Puerto Rico, Guam
• Cuba became a virtual U.S. protectorate
Why the War is Considered a Turning Point
• Ended Spanish colonial empire in America
• Saw emergence of US as a world Power

Reasons for Colonial Expansion
• Need for raw materials and markets
• Colonies would help U.S. naval strength
• Nationalism – show other nations how strong U.S. had become
• Missionaries sought to spread Christianity
Alfred Thayer Mahan
• Wrote The Influences of Sea Power upon History
• Argued for making U.S. into a world power
• U.S. needed a strong navy to protect its colonial interests.

• Philippines – Filipinos rebel and resist U.S. rule
• Hawaii – Queen Liliuokalani tried to take political power back from the American landowners. Sandford Dole led to provisional government while it worked out U.S. annexation.
• Pacific Islands – Guam, Samoa, Midway serve as refueling stations

China European powers establish “spheres of influence” in China
• John Hay’s Open Door Policy
• Boxer Rebellion (1900) – uprising by Boxers against Western influence in China; foreign interventions suppresses the uprising
Japan – Commodore Perry opens Japan to trade and ends Japan’s traditional isolation
• Treaty of Portsmouth 1905 – T. Roosevelt negotiated between Russia and Japan after Japan wins the Russo-Japanese War.

Reasons for U.S. Interest in Caribbean
• Hemispheric security
• America acquires Puerto Rico and establishes indirect control of
Cuba
• Protect its economic investments
• Panama Canal
Construction of Panama Canal
• President T. Roosevelt helps Panamanians rebel against Colombia for a Canal Zone
• U.S takes 10 years to construct canal, ends the need for a twoocean navy.
• Dr Walter Reed discovered that yellow fever was spread by mosquitoes and Dr William Gorgas ordered all swamps drained, vegetation cut down, and all standing water sprayed with oil to prevent breeding of mosquitoes
Caribbean as an “American Lake”

Roosevelt Corollary to Monroe Doctrine
• The US would act as international police power
• Big Stick Policy
Taft’s Dollar Diplomacy
• American investment to promote American foreign policy
Wilson’s “Watchful Waiting” Policy
• Refused to recognize Mexico’s new government
• Pancho Villa killed people in Columbus NM, Wilson sent the American Expeditionary Force led by General John
Pershing to apprehend him

European Causes: nationalism, imperialism, militarism, and alliance system
Spark starting WWI was the assassination of Archduke
Franz Ferdinand
Reason for US intervention in the War.
• Closer ties with Britain and France
• German actions and propaganda
• Zimmerman telegram/note
• Violation of Freedom of the Seas
• Sinking of the Lusitania/Sussex Pledge
• Use of unrestricted submarine warfare

New weapons and tactics:
• submarines * early tanks
• machine guns
• air planes
* poison gas
* trench warfare
Selective Service Act allowed national government to draft men to serve in the war
American Expeditionary Force US troops sent to Europe to defeat Germany
Battle of Argonne Forest major battle of WWI. Germany was defeated
• Alvin York was awarded the Congressional Medal of
Honor

Wilson’s Fourteen Points proposed by Wilson as a basis for the peace treaty
• Create new nation-states: Poland
• Break up Austria-Hungary
• Freedom of the Seas
• No secret treaties, open diplomacy
• League of Nations
Versailles and other treaties ended the war and dealt harshly with Germany
• Germany lost its colonies and had to pay reparations
• Austria-Hungary and Ottoman Turkey were broken up into separate nation-states
• League of Nations created

• Archduke Franz Ferdinand – his assassination sparked the start of WWI
• John Pershing – Commanded the American
Expeditionary Force during WWI
• Woodrow Wilson – US President during WWI, issued Fourteen Points, and strongly supported US participation in the League of Nations
• Henry Cabot Lodge – US Senator who led the fight against joining the League of Nations