Overview
AMSCO Topic 7.3, "The Spanish-American War and U.S. Foreign Policy to 1917," covers the war with Spain in 1898 and the burst of American foreign policy activity that followed it, from annexing the Philippines to building the Panama Canal. This chapter is the heart of Period 7's imperialism story. The short, decisive war turned the United States into a recognized world power with island territories in both the Caribbean and the Pacific, and the chapter traces how three presidents (Roosevelt, Taft, and Wilson) each put their own spin on managing that new empire.
The big exam takeaway: the Spanish-American War led to U.S. acquisition of island territories in the Caribbean and Pacific, deeper involvement in Asia, and the suppression of a nationalist movement in the Philippines. If you read the imperialism debates in AMSCO 7.2, this chapter is where those arguments get tested by real events.

Causes of the Spanish-American War
By 1898, jingoism (an intense nationalism demanding an aggressive foreign policy) was sweeping American public opinion, and a string of specific events pushed the country into war with Spain. Presidents Cleveland and McKinley both thought military action abroad was morally wrong and economically unsound, but public pressure won out.
The causes stacked up fast:
- Cuban revolt. Cuban nationalists renewed their fight against Spanish rule in 1895, sabotaging plantations to either push Spain out or pull the U.S. in. Spain sent General Valeriano Weyler ("the Butcher") with 100,000 troops; his civilian camps killed tens of thousands through starvation and disease.
- Yellow journalism. Joseph Pulitzer's New York World and William Randolph Hearst's New York Journal printed exaggerated and false accounts of Spanish atrocities, stoking war fever for humanitarian intervention.
- De Lôme Letter (1898). A leaked letter from Spanish minister Enrique Dupuy de Lôme insulted President McKinley. Americans read it as an official slap at national honor.
- Sinking of the Maine. On February 15, 1898, the USS Maine exploded in Havana harbor, killing 260 Americans. The yellow press blamed Spain, though experts later concluded the explosion was probably an accident.
McKinley's April war message to Congress listed four reasons to act: end the "barbarities" in Cuba, protect American lives and property there, end the damage to U.S. commerce, and end the "constant menace to our peace." Congress authorized war on April 20, 1898, attaching the Teller Amendment, which promised the U.S. would not take political control of Cuba and would let Cubans govern themselves once peace returned. Keep that promise in mind; the Platt Amendment is going to complicate it.
Fighting "A Splendid Little War"
The war lasted only a few months, from May to August 1898, which is why Secretary of State John Hay called it "a splendid little war." Oddly, the first shots came not in Cuba but in the Philippines, over 9,000 miles away.
The Philippines
Theodore Roosevelt, then assistant secretary of the navy, had already positioned Commodore George Dewey's fleet near the Philippines, a Spanish colony since the 1500s. On May 1, Dewey's all-steel ships destroyed the Spanish fleet in Manila Bay. U.S. troops, allied with Filipino rebels, captured Manila on August 13.
Cuba
Cuba was harder. A largely volunteer U.S. force landed in June, and disease proved deadlier than combat: fewer than 500 soldiers died in battle, but at least 5,000 died of malaria, typhoid, and dysentery. The most famous land action was the Rough Riders' charge up San Juan Hill, led by Roosevelt (who had quit his navy post to fight) and aided by veteran African American regiments. More decisive was the Navy destroying Spain's fleet at Santiago Bay on July 3. Without a navy, Spain asked for peace terms in early August.
The war also gave McKinley the pretext to complete the annexation of Hawaii in July 1898. Hawaii became a U.S. territory in 1900 and the fiftieth state in 1959.
The Treaty of Paris and the Philippine Question
The peace treaty signed in Paris on December 10, 1898, was more controversial than the war itself. Its terms: (1) Cuban independence, (2) U.S. acquisition of Puerto Rico and Guam, and (3) U.S. control of the Philippines for a $20 million payment to Spain.
Annexing the Philippines split the country. Anti-imperialists argued that ruling a heavily populated territory of a different race and culture violated the Declaration of Independence by denying Filipinos "life, liberty, and the pursuit of happiness," and would entangle the U.S. in Asian politics. The Senate ratified the treaty on February 6, 1899, by a vote of 57 to 27, just one vote over the required two-thirds.
Filipinos were outraged that independence from Spain meant rule by the United States instead. Emilio Aguinaldo, who had fought alongside U.S. troops against Spain, now led a guerrilla war against U.S. control. It took three years to suppress the insurrection, killing about 5,000 Americans and several hundred thousand Filipinos, mostly civilians who died of disease. This is the "suppression of a nationalist movement" the exam expects you to know.
Aftermath at home and in Cuba
- Anti-Imperialist League. Led by William Jennings Bryan, it rallied opposition to further Pacific expansion.
- Insular Cases (1901-1903). Did the Constitution follow the flag? The Supreme Court said no: constitutional rights did not automatically extend to territorial possessions, and Congress decided whether to grant them.
- Platt Amendment (1901). Despite the Teller Amendment, U.S. troops stayed in Cuba until 1901, and withdrawal came only after Cuba accepted terms requiring it to never sign treaties impairing its independence, to permit U.S. intervention to maintain order, and to allow U.S. naval bases, including a permanent one at Guantanamo Bay. In effect, Cuba became a U.S. protectorate.
- Election of 1900. McKinley (with Roosevelt as VP) beat Bryan by a larger margin than in 1896. Voters accepted the gold standard and the new territories.
- Recognition of U.S. power. Victory filled Americans with national pride, drew the South closer to the Union, and convinced European powers the U.S. was a first-class power.
The Open Door Policy and China
Secretary of State John Hay's Open Door notes (1899) asked the powers holding spheres of influence in China (Russia, Japan, Great Britain, France, and Germany) to give all nations equal trading privileges there. The replies were evasive, but since no nation rejected the idea, Hay simply declared the Open Door policy accepted, and the press hailed it as a diplomatic triumph.
In 1900, the Boxer Rebellion erupted: Chinese nationalists (the Society of Harmonious Fists) attacked foreign settlements and murdered dozens of Christian missionaries. U.S. troops joined an international force that crushed the rebellion in Peking (Beijing), and China was forced to pay a huge indemnity. Worried the powers might carve up China entirely, Hay sent a second round of notes committing the U.S. to preserving China's territorial integrity along with equal trade. These notes shaped U.S. policy in China for decades and would influence U.S.-Japan relations into the 1930s.
Big Stick, Dollar, and Moral Diplomacy
After McKinley's assassination by an anarchist in 1901, Theodore Roosevelt became president. His motto, "speak softly and carry a big stick," gave his aggressive foreign policy its name. Taft and Wilson followed with their own approaches, and the three-way comparison is a classic APUSH question.
Roosevelt's Big Stick
- Panama Canal. The Hay-Pauncefote Treaty (1901) got Britain to drop the 1850 Clayton-Bulwer Treaty's joint-control requirement. When Colombia balked at U.S. terms, Roosevelt orchestrated a revolt for Panama's independence in 1903, backed by the U.S. Navy. The new Panama signed the Hay-Bunau-Varilla Treaty granting the U.S. the 51-mile-long Canal Zone "in perpetuity." Built 1904-1914, the canal succeeded thanks to engineer George Goethals and Dr. William Gorgas, who eliminated the yellow-fever mosquitoes. Latin Americans deeply resented Roosevelt's tactics; Congress paid Colombia a $25 million indemnity in 1921, and the U.S. returned the Canal Zone to Panama in 1999.
- Roosevelt Corollary (1904). Rather than let European powers intervene in debt-ridden Latin American nations (like Santo Domingo) in violation of the Monroe Doctrine, Roosevelt declared the U.S. would intervene instead, occupying ports to collect customs taxes until debts were paid. Over the next 20 years, presidents used it to justify sending forces into Haiti, Honduras, the Dominican Republic, and Nicaragua, poisoning U.S.-Latin American relations.
- Asia. Roosevelt mediated the Russo-Japanese War with the Treaty of Portsmouth (1905), winning the Nobel Peace Prize in 1906. The "gentlemen's agreement" (1908) ended a crisis over San Francisco's segregation of Japanese American schoolchildren: Japan restricted worker emigration, California repealed its discriminatory laws. The Great White Fleet's world cruise (1907-1909) showed off U.S. naval power, and the Root-Takahira Agreement (1908) pledged mutual respect for Pacific possessions and the Open Door.
Taft's Dollar Diplomacy
William Howard Taft (1909-1913) swapped battleships for investors' dollars, promoting U.S. trade by supporting American enterprises abroad. He got U.S. bankers into a 1911 railroad agreement in China, but Russia and Japan shut the U.S. out of Manchuria in defiance of the Open Door. In Nicaragua, the U.S. intervened financially in 1911 and sent marines during a 1912 civil war; they stayed, with one short break, until 1933.
Wilson's Moral Diplomacy
Woodrow Wilson campaigned in 1912 promising a moral approach to foreign affairs, opposing imperialism, the big stick, and dollar diplomacy alike. In practice, Wilson still intervened militarily, especially in Mexico (the Tampico Incident, refusing to recognize General Victoriano Huerta, and sending John J. Pershing's expeditionary force after Pancho Villa). The Jones Act (1916) reflected his anti-imperialist side by moving the Philippines toward self-government. Wilson's foreign policy challenges lead straight into World War I in AMSCO 7.5.
Key Terms to Know
| Term | Why it matters |
|---|---|
| Jingoism | Intense nationalism demanding an aggressive foreign policy; the mood that pushed the U.S. toward war in 1898. |
| Yellow journalism | Sensationalist reporting by Pulitzer and Hearst that printed exaggerated Spanish atrocities and fueled war fever. |
| De Lôme Letter | Leaked Spanish letter criticizing McKinley that Americans took as a national insult. |
| Sinking of the Maine | The February 1898 explosion that killed 260 Americans; blamed on Spain, though likely an accident. |
| Teller Amendment | Congress's 1898 promise that the U.S. would not take political control of Cuba. |
| George Dewey | Commodore whose fleet destroyed the Spanish navy at Manila Bay on May 1, 1898. |
| Rough Riders | Roosevelt's volunteer regiment, famous for the San Juan Hill charge alongside African American regiments. |
| Treaty of Paris (1898) | Ended the war; gave the U.S. Puerto Rico, Guam, and the Philippines (for $20 million). |
| Emilio Aguinaldo | Filipino nationalist who led a three-year guerrilla war against U.S. annexation. |
| Anti-Imperialist League | Bryan-led group opposing further expansion as a betrayal of the Declaration of Independence. |
| Insular Cases | Supreme Court rulings (1901-1903) that the Constitution did not automatically follow the flag to territories. |
| Platt Amendment (1901) | Made Cuba a U.S. protectorate, allowing intervention and a naval base at Guantanamo Bay. |
| Open Door policy | John Hay's notes seeking equal trading rights for all nations in China and preserving China's territorial integrity. |
| Boxer Rebellion (1900) | Chinese nationalist uprising against foreigners, crushed by an international force including U.S. troops. |
| Roosevelt Corollary | TR's 1904 addition to the Monroe Doctrine claiming a U.S. right to intervene in Latin America. |
| Hay-Bunau-Varilla Treaty (1903) | Gave the U.S. the Canal Zone "in perpetuity" after Panama's U.S.-backed revolt against Colombia. |
| Dollar diplomacy | Taft's policy of using American investment instead of military force to extend U.S. influence. |
| Jones Act (1916) | Wilson-era law that moved the Philippines toward eventual self-government. |
Practice and Next Steps
Pair these notes with the Topic 7.3 Spanish-American War study guide, which frames the same content the way the exam tests it. The full set of AMSCO APUSH chapter notes keeps the rest of Unit 7 in one place.
To check yourself:
- Run APUSH guided practice questions on imperialism and turn-of-the-century foreign policy.
- Try a foreign-policy comparison prompt with FRQ practice and instant scoring. Comparing big stick, dollar, and moral diplomacy is a favorite setup.
- Look up any fuzzy terms in the APUSH key terms glossary.
Then keep moving through the unit with AMSCO 7.4 The Progressives, since domestic reform and overseas expansion were happening at the same time.
Frequently Asked Questions
What were the main causes of the Spanish-American War?
Four causes stacked up in 1898: the Cuban revolt against Spain and General Weyler's brutal camps, yellow journalism by Pulitzer and Hearst exaggerating Spanish atrocities, the leaked de Lôme Letter insulting President McKinley, and the explosion of the USS Maine in Havana harbor that killed 260 Americans. Jingoism, an aggressive nationalism, made the public eager to act on all of them.
What is the difference between the Teller Amendment and the Platt Amendment?
The Teller Amendment (1898) promised the U.S. would not take political control of Cuba and would let Cubans govern themselves after the war. The Platt Amendment (1901) walked that back: it made troop withdrawal conditional on Cuba accepting U.S. intervention rights and a permanent naval base at Guantanamo Bay, effectively turning Cuba into a U.S. protectorate.
What did the Treaty of Paris (1898) do?
Signed December 10, 1898, it recognized Cuban independence, gave the U.S. Puerto Rico and Guam, and transferred the Philippines to U.S. control for a $20 million payment to Spain. The Senate ratified it 57 to 27 in February 1899, just one vote over the required two-thirds, because Philippine annexation was so controversial.
How does the Spanish-American War show up on the APUSH exam?
The exam wants you to explain the war's effects: U.S. acquisition of island territories in the Caribbean and Pacific, increased involvement in Asia (the Open Door policy), and the suppression of the Filipino nationalist movement led by Emilio Aguinaldo. Comparing Roosevelt's big stick, Taft's dollar diplomacy, and Wilson's moral diplomacy is also a common short-answer and essay setup. Try a prompt with FRQ practice and instant scoring.
Did Spain actually sink the USS Maine?
Probably not. The yellow press accused Spain of deliberately blowing up the ship, but experts later concluded the explosion was most likely an accident. The episode is the classic APUSH example of how sensationalist journalism, not verified facts, pushed the U.S. toward war in 1898.
What was the Roosevelt Corollary to the Monroe Doctrine?
Theodore Roosevelt's 1904 declaration that the U.S., not European powers, would intervene in Latin American nations that couldn't pay their debts, occupying ports to collect customs taxes until creditors were satisfied. Over the next 20 years it justified sending U.S. forces into Haiti, Honduras, the Dominican Republic, and Nicaragua, and it badly damaged U.S. relations with Latin America.