In 1823 President James Monroe declared that European powers should not create new colonies in the Americas. For decades the Monroe Doctrine was more wish than policy, since only the British navy could enforce it. By 1900 things had changed. The United States had become an industrial giant, and Latin Americans began calling it the colossus of the north. The Cuban writer José Martí, who lived in New York for years, warned in his 1891 essay "Our America" that the neighbor to the north knew little of Latin America and might despise it, and urged Latin Americans to build governments from their own realities rather than copy foreign models.

The age of intervention

In 1898 the United States joined Cuba's war for independence and quickly defeated Spain. Puerto Rico became a US territory. Cuba became independent in name, but the Platt Amendment of 1901 gave the United States the right to intervene in Cuba and a naval base at Guantánamo Bay. In 1903 Washington backed Panama's break from Colombia to build a canal, which opened in 1914. In 1904 President Theodore Roosevelt announced what became known as the Roosevelt Corollary. Chronic wrongdoing or weakness in a Latin American country, he told Congress, might force the United States to the exercise of an international police power. In short, the Roosevelt Corollary claimed a US right to act as a regional police power.

Marines followed. US forces occupied Nicaragua for most of the years from 1912 to 1933, Haiti from 1915 to 1934, and the Dominican Republic from 1916 to 1924, often to collect debts or protect investments. In Nicaragua the guerrilla leader Augusto Sandino fought the Marines for six years. American companies such as United Fruit owned vast plantations, railways and ports in Central America. The writer O. Henry coined the phrase "banana republic" in a 1904 book about a fictional Central American country run for foreign fruit companies. In 1933 Franklin Roosevelt changed course: the Good Neighbor Policy promised an end to US armed intervention in Latin America. That promise would be tested during the Cold War.

The Mexican Revolution

In 1910 Porfirio Díaz, now 80, claimed another rigged election victory. Francisco Madero, a wealthy reformer, called for revolt, and Díaz fled into exile in 1911. Madero proved too cautious for the rural poor. In the south, Emiliano Zapata's Plan of Ayala demanded the return of land to the villages that had lost it under Díaz. In the north, Pancho Villa led armies of cowboys, miners and farmers. Madero was murdered in a 1913 coup by General Victoriano Huerta, and the revolution became a many-sided civil war. Perhaps a million or more people died or fled before the fighting wound down around 1920.

The winners wrote the Constitution of 1917, which wrote land and labor rights into law. Article 27 made land and the minerals beneath it the property of the nation and allowed land redistribution; Article 123 guaranteed an eight hour day, the right to strike and other protections. It was one of the first constitutions anywhere to promise social rights alongside political ones. Reform came slowly until Lázaro Cárdenas, president from 1934 to 1940, redistributed huge amounts of land and in 1938 nationalized Mexico's oil industry, which had been owned by British and American firms. The revolution's party governed Mexico without a break for over seventy years, winning elections that were often unfair, until it lost the presidency in 2000.

The Cuban Revolution

In 1952 Fulgencio Batista seized power in Cuba in a coup. A young lawyer, Fidel Castro, led a guerrilla war from the Sierra Maestra mountains, and on 1 January 1959 Batista fled. The new government nationalized land, sugar mills and American-owned businesses, and the United States responded with an embargo that still stands. Castro allied with the Soviet Union and declared the revolution socialist. Supporters point to real gains: a 1961 campaign that sent young volunteers into the countryside to teach reading, and free schooling and health care for all. Even many critics grant the revolution a sharp rise in literacy and health. Critics point to a one-party state, the execution and imprisonment of opponents, no free press or free elections, and over a million Cubans who emigrated.

Worked example: weighing a revolution

How should a student judge the Cuban Revolution? One shortcut is to pick a side and collect only the evidence that helps it. A better method is to separate questions. Did literacy and life expectancy rise? The evidence says yes, and Cuba's health statistics were long among the best in Latin America, though some data came from a government that controlled all statistics. Were political freedoms crushed? The evidence also says yes, from the trials of 1959 to the jailing of dissidents and journalists decades later. Could the gains have come without the repression? Costa Rica, a democracy that abolished its army in 1948, reached similar health and literacy levels, which suggests they could. Was US hostility partly to blame for Cuba's hardships? Probably, though it does not explain the lack of free speech. Answering each question on its own evidence keeps human rights at the center for every regime, of the left or the right.