Explain how overseas expansion, the Spanish-American War and World War I made the United States a world power

Learning goal: Explain how, as a result of overseas expansion, the Spanish-American War and World War I, the United States emerged as a world power between the 1890s and 1918. Define "world power," trace the three developments with accurate dates, and weigh the arguments Americans made for and against expansion.

What "world power" means. A world power is a country whose military, economic and diplomatic strength lets it influence events far beyond its own region. In 1890 the United States was already a large industrial economy, but it had a small army and navy, few overseas possessions and little role in great-power diplomacy. By 1919 its president was helping write the peace settlement in Paris, its navy was among the largest in the world, and it had become a creditor nation to which European governments owed large war debts. The standard names three causes of that change.

Overseas expansion. Several forces pushed Americans to look outward in the 1890s. Industrial output was growing faster than home demand, and business leaders sought foreign markets. The naval officer Alfred Thayer Mahan argued in The Influence of Sea Power upon History (1890) that great nations needed a strong navy, coaling stations and overseas bases. Some Americans believed in a duty to spread their institutions and religion, often in language that assumed the racial superiority of white Americans. Others, the anti-imperialists, argued that ruling other peoples without their consent violated the principles of the Declaration of Independence.

Hawaii is the key case. Sugar planters and businessmen of American descent, some born in the United States and some in Hawaii, had gained great economic and political power in the Hawaiian Kingdom. In January 1893, a group of them overthrew Queen Liliʻuokalani, with United States Marines landed from an American warship. President Grover Cleveland opposed annexation, but in 1898 Congress annexed Hawaii by a joint resolution. In 1899 the United States and Germany divided the Samoan islands, and in 1899–1900 Secretary of State John Hay's Open Door notes asked the powers with spheres of influence in China to allow equal trading access for all.

The Spanish-American War, 1898. As the lesson on historical thinking showed, long-term causes (American interests in Cuba, sympathy for the Cuban independence war that began in 1895, reports of suffering in Spanish camps, naval ambitions) combined with short-term triggers (the de Lôme letter and the Maine explosion of February 15, 1898). Congress declared war on April 25, 1898. The Teller Amendment stated that the United States would not annex Cuba. The war was short. On May 1, 1898, Commodore George Dewey's squadron destroyed the Spanish fleet in Manila Bay in the Philippines; in July, American forces won at San Juan Hill and Santiago in Cuba, and the Spanish Caribbean fleet was destroyed. Under the Treaty of Paris, signed December 10, 1898, Spain gave up Cuba and ceded Puerto Rico, Guam and the Philippines to the United States, which paid Spain 20 million dollars.

The war's results made the United States a colonial power. Filipinos who had fought Spain for independence resisted American rule in the Philippine-American War, which the United States declared over in 1902, though fighting continued in some regions after that. About 20,000 Filipino soldiers were killed, and estimates of Filipino civilian deaths from violence, famine and disease run as high as 200,000; more than 4,000 American soldiers died. The Platt Amendment (1901) kept Cuba formally independent but gave the United States the right to intervene and required Cuba to sell or lease land for naval stations, which led to the 1903 lease of Guantánamo Bay. In the Caribbean, President Theodore Roosevelt's Roosevelt Corollary (1904) to the Monroe Doctrine claimed a right to act as an international police power in Latin America. Roosevelt's readiness to back diplomacy with naval force is called Big Stick diplomacy, from his saying "speak softly and carry a big stick." After the United States supported Panama's independence from Colombia in 1903, it built the Panama Canal, which opened on August 15, 1914, connecting its Atlantic and Pacific fleets.

World War I. War began in Europe in the summer of 1914. The United States declared neutrality, but American trade and loans flowed mostly to Britain and France, and Germany's submarine attacks on shipping killed Americans. A German submarine sank the British liner Lusitania on May 7, 1915; more than 1,100 people died, among them 128 Americans. On February 1, 1917, Germany resumed unrestricted submarine warfare, and in March the American press published the Zimmermann Telegram, a German proposal inviting Mexico into an alliance against the United States. President Woodrow Wilson asked Congress for war on April 2, 1917, saying "The world must be made safe for democracy," and Congress declared war on April 6.

The United States raised an army through the Selective Service Act of 1917 and sent about two million soldiers to France in the American Expeditionary Forces under General John J. Pershing. American troops fought in major offensives in 1918, including the Meuse-Argonne. More than 100,000 Americans died in the war, many of them from disease, especially influenza. The armistice took effect on November 11, 1918. In January 1918 Wilson had set out his Fourteen Points, a plan for peace that included freedom of the seas, reduced armaments, self-determination for some peoples and an association of nations.

A worked model: measuring "world power." Test the claim "By 1919 the United States was a world power" against three measures. Military: a navy expanded since the 1890s, overseas bases in Hawaii, Guam, the Philippines and Guantánamo, and an army that had fought in France. Economic: the largest industrial economy and a creditor to its wartime allies. Diplomatic: Wilson's Fourteen Points framed the peace talks and he attended the Paris conference in person. All three measures point the same way, so the claim is well supported; whether that power was used wisely is a separate, interpretive question.

The misconception to avoid. Students often date American world power only to World War II. The evidence shows it emerged between the 1890s and 1918; what came after World War I, as the next lesson explains, was a debate about how to use it.

Worked cause sort: For the Spanish-American War, sort into economic, strategic, humanitarian and trigger causes. Economic: American investments and trade in Cuban sugar. Strategic: Mahan's argument for naval bases. Humanitarian: reports of Cubans dying in Spanish camps. Triggers: the de Lôme letter (February 9, 1898) and the Maine (February 15, 1898). Reasoning: no single category explains the declaration of April 25, 1898; the combination does.

Worked treaty reading: Treaty of Paris, December 10, 1898. Spain gives up Cuba; cedes Puerto Rico, Guam and the Philippines; receives 20 million dollars. Consequences: the United States now governs overseas peoples without their consent, which leads to the Philippine-American War and to the anti-imperialist debate over whether this matches the Declaration's principle of consent. The skipped step: connecting the terms to the domestic argument they created.

Worked sequence to war in 1917: 1914 war begins, U.S. neutral; May 7, 1915 Lusitania sunk with 128 Americans among the dead; February 1, 1917 unrestricted submarine warfare resumes; March 1917 Zimmermann Telegram published; April 2, 1917 Wilson asks for war; April 6, 1917 Congress declares war. Long-term cause: trade and loans tying the United States to Britain and France. Short-term causes: renewed submarine warfare and the telegram.

Power ledger: Make a table with rows for Hawaii (1893, 1898), the Treaty of Paris (1898), the Philippine-American War (1899–1902), the Platt Amendment (1901), the Roosevelt Corollary (1904), the Panama Canal (1914) and World War I (1917–1918). Columns: date; what the United States gained or did; military, economic or diplomatic measure of power; who opposed or resisted, and on what grounds.

Independent performance: Write a 450-word argument answering, "How did the United States become a world power between 1893 and 1918?" Success criteria: defines world power; explains all three causes in the standard with accurate dates; includes the perspective of at least one people affected by American expansion (Hawaiians, Filipinos, Cubans or Puerto Ricans); explains why the United States entered World War I with long-term and short-term causes; and states a thesis that weighs which cause mattered most, labeled as interpretation.

Debate brief: Prepare a short brief for a class debate on annexing the Philippines in 1899. Give two arguments an expansionist made and two an anti-imperialist made, each tied to a fact from the lesson, and end with one sentence stating how Filipinos who had fought Spain viewed American rule.