AP UNITED STATES HISTORY • PERIOD 7: 1890–1945

The Spanish–American War

How a brief 1898 conflict transformed the United States into a global imperial power.

Historical Context & Motivation

The Spanish–American War of 1898 marked a decisive turning point in the trajectory of American foreign policy, propelling the United States from a continental republic focused largely on internal expansion to a nascent imperial power with overseas territories spanning the Caribbean and the Pacific. The war grew out of a convergence of factors—humanitarian outrage over Spain's brutal suppression of the Cuban independence movement, intense economic interests in the sugar-rich island, and a rising tide of jingoistic nationalism fueled by the popular press. Understanding the war requires situating it within the broader context of late-nineteenth-century imperialism, when European powers were carving up Africa and Asia while American policymakers debated whether the United States should join the scramble for colonies.

Cuba had been in revolt against Spanish colonial rule intermittently since the Ten Years' War (1868–1878), and a renewed insurrection erupted in 1895 under leaders such as José Martí. Spain responded with a reconcentration policy implemented by General Valeriano Weyler, forcibly relocating Cuban civilians into fortified camps where disease and starvation killed tens of thousands. Reports of these atrocities reached American newspapers, where publishers William Randolph Hearst and Joseph Pulitzer sensationalized the suffering to boost circulation—a practice critics labeled yellow journalism. The combination of genuine humanitarian concern and media manipulation created enormous public pressure on the McKinley administration to intervene.

1895
Cuban Revolt Resumes
José Martí and Cuban revolutionaries reignite the independence struggle against Spanish colonial rule, prompting Spain's harsh reconcentration policy under General Weyler.
1896–97
Yellow Press Fuels Outrage
Hearst's New York Journal and Pulitzer's New York World publish lurid accounts of Spanish atrocities, amplifying public sympathy for Cuba and pressuring policymakers toward intervention.
Feb 1898
The De Lôme Letter & USS Maine
A leaked letter from Spanish Ambassador de Lôme insults President McKinley. Days later, the USS Maine explodes in Havana Harbor, killing 266 sailors and igniting the rallying cry 'Remember the Maine!'
Apr 1898
War Declared
Congress passes a joint resolution demanding Spanish withdrawal from Cuba. The Teller Amendment pledges the U.S. will not annex the island. Spain declares war on April 24; the U.S. reciprocates on April 25.
Dec 1898
Treaty of Paris
Spain cedes the Philippines, Guam, and Puerto Rico to the United States and relinquishes sovereignty over Cuba, marking the emergence of the U.S. as a colonial power.

The central question framing this lesson is both strategic and ideological: how did a war ostensibly fought to liberate Cuba from colonial oppression result in the United States acquiring its own overseas empire—and what does that transformation reveal about the competing visions of American identity at the turn of the twentieth century?

Core Causes & Driving Principles

Historians typically identify several interlocking causes of the Spanish–American War, none of which alone would have been sufficient to drive the nation to armed conflict. Rather, these factors reinforced one another, creating a self-amplifying cycle of public outrage, strategic calculation, and ideological justification that made war appear both righteous and inevitable to a wide cross-section of American opinion.

1

Yellow Journalism

Sensationalist reporting by Hearst and Pulitzer distorted events in Cuba, fabricating or embellishing stories of Spanish cruelty to boost circulation. This media environment manufactured public consent for war and constrained McKinley's diplomatic options.
2

Economic Interests

American investors held roughly $50 million in Cuban sugar plantations and mines, while annual U.S.–Cuban trade exceeded $100 million. The ongoing insurgency disrupted these investments, creating powerful business lobbies for intervention or at least stability.
3

Strategic & Naval Ambitions

Alfred Thayer Mahan's The Influence of Sea Power upon History (1890) argued that national greatness required a powerful navy, coaling stations, and overseas bases. Cuba and the Philippines fit neatly into this strategic vision of naval supremacy.
4

Humanitarian & Ideological Impulses

Many Americans genuinely sympathized with Cuban rebels fighting for self-determination, viewing the cause through the lens of their own revolutionary heritage. Concepts like the 'White Man's Burden' and Social Darwinism added a racialized civilizing-mission narrative.
5

The USS Maine Catalyst

The mysterious explosion that sank the Maine on February 15, 1898 provided the emotional trigger. Although the cause remains debated—likely an internal coal fire—the press and public blamed Spain. 'Remember the Maine, to hell with Spain!' became a war cry.
KEY TAKEAWAY
Think of the causes of the Spanish–American War like the ingredients for a chemical reaction: economic interests provided the fuel, humanitarian outrage supplied the oxidizer, strategic ambitions shaped the container, and the sinking of the Maine served as the spark. Remove any single element and war might have been averted—but together they produced an explosion of imperialist energy that propelled the United States onto the world stage.

Visual Explanation: Causes-to-Consequences Flowchart

This flowchart traces the path from the multiple causes of the war (top row), through the catalytic sinking of the Maine (red), to the declaration of war (amber), the Treaty of Paris (green), and the three major consequences that emerged in the war's aftermath (bottom row). Note how the Teller Amendment promised Cuban independence while the actual outcomes included extensive U.S. imperial control.

The diagram above illustrates a critical interpretive framework for AP exam analysis: the gap between stated war aims and actual outcomes. The Teller Amendment explicitly disclaimed any U.S. intention to annex Cuba, yet the postwar settlement—encompassing the Platt Amendment, the annexation of the Philippines, Guam, and Puerto Rico—revealed that the war had served expansionist objectives well beyond Cuban liberation. This disjunction between rhetoric and reality became the central ammunition for the anti-imperialist movement and remains a key analytical theme in AP essays on this period.

The War's Military Course & Key Decisions

Two-Theater Strategy

The Spanish–American War was fought simultaneously in two widely separated theaters—the Caribbean and the Pacific—reflecting the dual nature of American strategic ambitions. In the Pacific, Commodore George Dewey's Asiatic Squadron had been pre-positioned in Hong Kong on orders from Assistant Secretary of the Navy Theodore Roosevelt, who had cabled Dewey in February 1898—weeks before the declaration of war—to prepare for offensive operations against the Spanish Philippines. This decision reveals the premeditated strategic dimension of the conflict that extended far beyond Cuban liberation.

Pacific Theater: The Battle of Manila Bay

On May 1, 1898, Dewey's squadron steamed into Manila Bay and destroyed the entire Spanish Pacific fleet in a matter of hours, suffering minimal American casualties. The Battle of Manila Bay was a decisive demonstration of American naval modernization and validated Mahan's thesis about the strategic importance of sea power. Filipino insurgents under Emilio Aguinaldo had been fighting Spain independently, and Dewey initially cooperated with them, only for the relationship to sour when it became clear that the United States intended to retain the Philippines rather than grant independence. This broken promise would lead directly to the Philippine–American War (1899–1902).

Caribbean Theater: Santiago Campaign

In Cuba, American forces—including Theodore Roosevelt's celebrated Rough Riders and the often-overlooked Buffalo Soldiers of the 9th and 10th Cavalry—fought the battles of El Caney and San Juan Hill on July 1, 1898. The subsequent destruction of Spain's Caribbean fleet attempting to break the U.S. naval blockade at Santiago sealed Spain's defeat. The land campaign was marked by logistical chaos, inadequate supplies, and rampant tropical disease—more American soldiers died of typhoid and dysentery than from combat. Secretary of State John Hay famously called it a 'splendid little war,' a characterization that glossed over the significant suffering on all sides and the complex imperial aftermath that followed.

This dual-theater timeline shows how Pacific operations (cyan) began even before the formal declaration of war (amber), while Caribbean operations (pink) dominated the summer months. The entire conflict from declaration to armistice lasted barely four months.

Treaty of Paris & Imperial Acquisitions

The Treaty of Paris, signed on December 10, 1898, and ratified by the Senate in February 1899 by a narrow margin of 57–27 (just one vote more than the required two-thirds), redrew the map of American power. Spain ceded the Philippines, Guam, and Puerto Rico to the United States; the U.S. paid Spain $20 million for the Philippines. Cuba gained nominal independence but was placed under American military occupation until 1902, and the subsequent Platt Amendment (1901) effectively made the island a U.S. protectorate by granting America the right to intervene in Cuban affairs and establishing the naval base at Guantánamo Bay.

Territorial outcomes of the Spanish–American War and related acquisitions
TerritoryStatus After 1898Key Developments
CubaIndependent republic under Platt Amendment constraints (1901–1934)U.S. military occupation 1898–1902; Platt Amendment allowed U.S. intervention; Guantánamo Bay leased
PhilippinesU.S. territory (1898–1946)Philippine–American War (1899–1902) killed over 200,000 Filipinos; independence granted in 1946
Puerto RicoU.S. territory (Foraker Act 1900; Jones Act 1917)U.S. citizenship granted 1917; remains an unincorporated territory to this day
GuamU.S. territory (unincorporated)Served as a Pacific naval coaling station; strategic value confirmed in WWII
Hawai'iAnnexed July 1898 (separate from Treaty)War demonstrated Hawai'i's strategic necessity as a mid-Pacific refueling station, accelerating annexation

The Insular Cases (1901 and after) were a series of Supreme Court decisions that addressed the constitutional status of these new territories. The Court ruled that the Constitution did not automatically extend full rights to inhabitants of unincorporated territories—establishing the doctrine that 'the Constitution follows the flag, but doesn't quite catch up.' This legal framework allowed the United States to govern an empire while maintaining the fiction that it remained a republic of equal citizens, a tension that persists in the status of Puerto Rico and other territories today.

Worked Example: Analyzing a Primary Source

AP U.S. History exams frequently present primary-source excerpts related to the Spanish–American War and require students to identify the author's perspective, contextualize the document, and connect it to broader themes. Below is a worked example using the kind of analytical process you should employ on SAQs and DBQs.

📜 SOURCE EXCERPT
"We assert that no nation can long endure half republic and half empire, and we warn the American people that imperialism abroad will lead to despotism at home." — Democratic Party Platform, 1900

Prompt: Identify the speaker's argument, explain the historical context, and evaluate the extent to which this position reflected broader American sentiment in 1900.

Analytical Breakdown
1
Step 1 — Identify the ArgumentThe Democratic platform argues that imperialism is fundamentally incompatible with republican government. By invoking Lincoln's 'house divided' rhetoric ('half republic and half empire'), the authors draw an explicit parallel between the slavery crisis and the imperial crisis, suggesting that empire will corrupt domestic democratic institutions just as slavery once threatened to.
Central claim: imperialism abroad → despotism at home
2
Step 2 — Establish Historical ContextThis platform was written during the 1900 presidential election, in which Democrat William Jennings Bryan challenged incumbent Republican William McKinley. The Treaty of Paris had been ratified in February 1899, and the Philippine–American War was already raging, with reports of American atrocities and Filipino civilian deaths reaching the press. The Anti-Imperialist League, whose members included Mark Twain, Andrew Carnegie, and former president Grover Cleveland, had been actively campaigning against territorial expansion.
Context: post-Treaty of Paris; Philippine–American War underway; active anti-imperialist movement
3
Step 3 — Evaluate Broader SentimentWhile the anti-imperialist position was articulated by prominent intellectuals and politicians, McKinley won the 1900 election decisively, suggesting that a majority of the voting public either supported imperialism, prioritized other issues (such as the gold standard and economic prosperity), or accepted the argument that the U.S. had a 'civilizing mission.' The anti-imperialist critique was further weakened by its own internal contradictions—some opponents of empire based their arguments on white supremacist grounds, objecting to the incorporation of nonwhite populations rather than defending Filipino self-determination.
Evaluation: anti-imperialism was vocal but ultimately a minority position in electoral politics
4
Step 4 — Connect to Broader ThemesThis document connects to the AP theme of American identity and self-governance (NAT). The debate over empire forced Americans to confront whether their founding principles of consent of the governed applied universally or only to white citizens. It also links to the theme of America's evolving role in the world (WOR), foreshadowing twentieth-century debates over interventionism, from the Philippines to Vietnam to Iraq.
AP Themes: NAT (American identity), WOR (global role), PCE (political debate over expansion)

Imperialists vs. Anti-Imperialists

The Spanish–American War ignited one of the most consequential debates in American political history: should the United States become an imperial power? This question cut across party lines and produced unusual alliances, pitting expansionist Republicans like Theodore Roosevelt and Henry Cabot Lodge against anti-imperialist Republicans like Andrew Carnegie, while Democrats split between Bryan's anti-empire stance and Southern Democrats who supported expansion for commercial reasons.

Comparing imperialist and anti-imperialist positions across multiple dimensions
DimensionImperialist ArgumentsAnti-Imperialist Arguments
EconomicNew markets for surplus industrial goods; access to raw materials; coaling stations for Pacific trade with ChinaEmpire is expensive to maintain; military garrisons drain the treasury; trade can occur without political control
StrategicNaval bases protect shipping lanes; fulfills Mahan's doctrine; keeps European powers from filling vacuumsOverseas commitments entangle the U.S. in foreign disputes; violates Washington's Farewell Address warning
Ideological'White Man's Burden' (Kipling); Social Darwinism; duty to 'civilize' and Christianize 'lesser' peoplesDeclaration of Independence asserts government by consent; imperialism contradicts self-determination; racial paternalism is morally bankrupt
ConstitutionalConstitution gives Congress power to acquire territory; precedent set by Louisiana Purchase and Mexican CessionNo constitutional provision for governing permanent colonies of subjects denied citizenship; 'republic cannot be an empire'
Key FiguresTheodore Roosevelt, Henry Cabot Lodge, Albert Beveridge, Alfred Thayer Mahan, Josiah StrongMark Twain, Andrew Carnegie, William Jennings Bryan, Grover Cleveland, Carl Schurz, Jane Addams
KEY TAKEAWAY
The imperialism debate was not a simple two-sided argument. Some anti-imperialists opposed annexation on racist grounds—they feared incorporating nonwhite populations into the body politic—while some imperialists genuinely believed in a benevolent civilizing mission. On the AP exam, demonstrating awareness of this complexity—that both sides contained contradictions—will strengthen any argument you construct in a DBQ or LEQ.

Legacy & Connections to Later U.S. Foreign Policy

The Spanish–American War established patterns that would recur throughout twentieth-century American foreign policy. The war demonstrated that a combination of media-driven public outrage, strategic calculation, and ideological framing could propel the nation into overseas military action—a pattern visible in interventions from the Philippine–American War through the Vietnam War and beyond. The Roosevelt Corollary to the Monroe Doctrine (1904), the Open Door Policy in China, and the construction of the Panama Canal all flowed logically from the strategic position the U.S. established in 1898.

Patterns established by the Spanish–American War that recur in later U.S. foreign policy
FeatureSpanish–American War (1898)Later 20th-Century Parallels
Media RoleYellow journalism sensationalized events to build public support for interventionTelevision coverage shaped Vietnam opinion; 24-hour news cycles influenced Gulf War and Iraq War support
Catalyst EventSinking of USS Maine (cause still debated)Gulf of Tonkin Incident (1964, later shown to be largely fabricated); 9/11 attacks (2001)
Stated vs. Actual GoalsLiberation of Cuba; actual outcome was imperial acquisition across two oceansCold War interventions framed as defending freedom often installed authoritarian regimes; Iraq War WMD claims
Domestic DebateAnti-Imperialist League vs. expansionistsAnti-war movements against Vietnam, Iraq; ongoing debates about humanitarian intervention
CounterinsurgencyPhilippine–American War (brutal guerrilla conflict, 1899–1902)Vietnam, Afghanistan, and Iraq insurgencies followed similar patterns of asymmetric warfare

For the AP exam, these connections are especially valuable in long essay questions that ask you to trace continuities and changes over time in American foreign policy. The Spanish–American War is best understood not as an isolated event but as the foundational moment when the United States crossed the threshold from continental expansion (Manifest Destiny) to overseas imperialism—a transition that fundamentally reshaped the nation's relationship with the rest of the world for the century that followed.

Practice Problems

1
Which of the following best explains why the Teller Amendment was included in the congressional resolution authorizing war against Spain in 1898?
2
The Supreme Court's rulings in the Insular Cases (1901) were most significant because they:
PROBLEM 3INTERMEDIATE
Answer parts (a), (b), and (c). (a) Briefly describe ONE specific cause of the Spanish–American War. (b) Briefly explain how the outcome of the Spanish–American War represented a continuity in United States expansion. (c) Briefly explain how the outcome of the Spanish–American War represented a change in United States expansion.
PROBLEM 4APPLIED
Use the two documents below and your knowledge of United States history to answer the following question. Document 1: Senator Albert Beveridge, speech to the U.S. Senate, January 9, 1900: "The Philippines are ours forever... And just beyond the Philippines are China's illimitable markets. We will not retreat from either... The Pacific is our ocean... Where shall we turn for consumers of our surplus? Geography answers the question. China is our natural customer." Document 2: Platform of the American Anti-Imperialist League, October 1899: "We hold that the policy known as imperialism is hostile to liberty and tends toward militarism, an evil from which it has been our glory to be free. We regret that it has become necessary in the land of Washington and Lincoln to reaffirm that all men, of whatever race or color, are entitled to life, liberty, and the pursuit of happiness." Question: Evaluate the extent to which economic considerations, rather than ideological principles, drove the debate over American imperialism following the Spanish–American War.
PROBLEM 5CRITICAL THINKING
Evaluate the extent to which the Spanish–American War represented a turning point in United States foreign policy. In the development of your argument, explain what changed and what stayed the same from the period before the war to the period after.

Summary

The Spanish–American War of 1898 arose from a volatile mixture of yellow journalism, economic interests in Cuban sugar, Mahan's naval strategy, humanitarian sympathy for Cuban rebels, and the catalytic sinking of the USS Maine. The Teller Amendment disclaimed any intent to annex Cuba, but the Treaty of Paris gave the United States the Philippines, Guam, and Puerto Rico, while the Platt Amendment made Cuba a de facto protectorate.

The war's aftermath sparked a fierce domestic debate between imperialists (Roosevelt, Lodge, Beveridge) and anti-imperialists (Twain, Carnegie, Bryan), while the Insular Cases established a constitutional framework for governing colonial subjects without extending full rights. The Philippine–American War (1899–1902) revealed the brutal costs of empire. On the AP exam, the Spanish–American War is best analyzed as both a continuity of Manifest Destiny's territorial ambitions and a turning point toward overseas empire, global military projection, and the interventionist foreign policy that would define the twentieth century.

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