A history of U.S. intervention in Latin America by each of the major occurrences:
1823: The Monroe Doctrine declares Latin America to be in the United States' "sphere of influence."
1846: The U.S. causes war with Mexico and acquires half of its territory, including Texas and California.
1855: U.S. adventurer William Walker invades Nicaragua with a private army, declares himself president, and rules for 2 years.
1898: The U.S. declares war on Spain beginning the Spanish-American War, and as a result it gets Guam, Puerto Rico, the Philippines and Hawaii.
1901: With the Platt Amendment, the U.S. declares its rights to intervene in Cuban affairs.
1903: The U.S. encourages Panama's independence from Colombia in order to acquire the Panama Canal rights.
1905: The Roosevelt Corollary to the Monroe Doctrine declares the U.S. to be the policeman of the Caribbean; the Dominican Republic is placed under a customs receivership.
1912: U.S. Marines invade Nicaragua and occupy the country almost continuously until 1933.
1914: Mexican refusal to salute the U.S. flag provokes the shelling of Veracruz by a U.S. battleship and the capture of parts of the city by U.S. Marines.
1933: U.S. Marines finally leave Nicaragua, but are replaced by a well-trained and well-armed National Guard under the control of Anastasio Somoza.
1954: The CIA engineers the overthrow of the democratically-elected government of Guatemala; 30 years of military dictatorship, repression, and violence follow.
1961: The U.S. attempts to overthrow the revolutionary Cuban government at the Bay of Pigs.
1965: Johnson sends 22,000 troops to the Dominican Republic to combat the constitutional forces trying to regain power.
1973: The CIA helps overthrow the democratic government of Allende in Chile in favor of a bloody dictatorship.
1981: The Reagan Administration begins the war against Nicaragua.
1983: The U.S. invades Grenada to take over a popular government.
1989: The U.S. invades Panama to arrest accused drug dealer Manual Noriega.
1990: The U.S. intervenes in the Nicaraguan election process through covert and overt means.
The Spanish-American War
In 1898 the United States decared war on Spain. The things that led up to the Spanish-American War were many. The mysterious explosion of the Maine, a U.S. battleship, was a major influence on the war. Also yellow journalism was part of the Spanish-American War. Yellow journalism was the hype of the war. The journalist would say things to get the Americans rowdy and ready to fight.