Following the attacks, President Bush's job approval rating soared to 90%.[174] On September 20, 2001, the U.S. president spoke before the nation and a joint session of the United States Congress, regarding the events of that day, the intervening nine days of rescue and recovery efforts, http://en.wikipedia.org/wiki/September_11_attacks#Immediate_response
The U.S. government viewed involvement in the war as a way to prevent a communist takeover of South Vietnam and part of their wider strategy of containment. http://en.wikipedia.org/wiki/Vietnam_War
World War II, or the Second World War[1] (often abbreviated as WWII or WW2), was a global military conflict lasting from 1939 to 1945, which involved most of the world's nations, including all of the great powers: eventually forming two opposing military alliances, the Allies and the Axis. http://en.wikipedia.org/wiki/World_War_II
World War I (WWI) or First World War (called at the time the Great War) was a major war centered on Europe that began in the summer of 1914. The fighting ended in November 1918. http://en.wikipedia.org/wiki/World_War_I
The Spanish–American War was a conflict in 1898 between Spain and the United States. It ultimately ended with the Americans defeating the Spaniards http://www.loc.gov/rr/hispanic/1898/intro.html
The Monroe Doctrine is a policy of the United States introduced on December 2, 1823. It stated that further efforts by European countries to colonize land or interfere with states in the Americas would be viewed as acts of aggression requiring U.S. intervention. http://en.wikipedia.org/wiki/Monroe_Doctrine
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