President William McKinley asks Congress to declare war on Spain on April 20, 1898.

In 1895, Cuba, located less than 100 miles south of the United States, attempted to overthrow Spanish colonial rule. The rebels received financial assistance from private U.S. interests and used America as a base of operations from which to attack. The Spanish military responded with brutal force; approximately 100,000 Cuban civilians died in wretched conditions within Spanish concentration camps between 1895 and 1898. McKinley originally tried to avoid an armed conflict with Spain, but the American media, led by newspaper baron Randolph Hearst, lambasted McKinley as weak and whipped up popular sentiment for a war to give Cubans their independence.

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On February 17, 1898, the battleship USS Maine, moored in Havana’s harbor, sank after being rocked by two explosions; 252 men onboard were killed. Hawks in the media and within the government immediately blamed Spain, and President McKinley, abandoning his hopes for neutrality in the Cuban-Spanish conflict, bowed to Congressional calls for war. (It was later discovered that the explosion was caused by the spontaneous ignition of faulty ammunitions onboard the Maine.)

Swift, successful naval battles in the Philippines and the army’s capture of Santiago and Puerto Rico, led by future President Theodore Roosevelt and his band of Rough Riders, ended what became known as the Spanish-American War in four months with relatively few casualties. The quick success boosted American confidence, leading to further intervention in foreign affairs in an attempt to liberate what were, in the eyes of the U.S. government, at least, oppressed nations yearning for democracy and independence. Although contemporaries of McKinley and Roosevelt called it a splendid little war, the Spanish-American War is now viewed by most historians as a war of American imperialism.