American Imperialism

“American imperialism” is a term that refers to the economic, military, and cultural influence of the United States internationally.

Key Takeaways

Social DarwinismAmerican ExceptionalismThe American Anti-Imperialist LeagueAmerican Imperialism

Expansion and Power

“American imperialism” is a term that refers to the economic, military, and cultural influence of the United States on other countries. First popularized during the presidency of James K. Polk, the concept of an “American Empire” was made a reality throughout the latter half of the 1800s. During this time, industrialization caused American businessmen to seek new international markets in which to sell their goods. In addition, the increasing influence of social Darwinism led to the belief that the United States was inherently responsible for bringing concepts such as industry, democracy, and Christianity to less developed “savage” societies. The combination of these attitudes and other factors led the United States toward imperialism.

“Ten Thousand Miles from Tip to Tip”: “Ten Thousand Miles from Tip to Tip,” refers to the extension of U.S. domination (symbolized by a bald eagle) from Puerto Rico to the Philippines. The cartoon contrasts the 1898 representation with that of the United States in 1798.

American imperialism is partly rooted in American exceptionalism, the idea that the United States is different from other countries due to its specific world mission to spread liberty and democracy. This theory often is traced back to the words of 1800s French observer Alexis de Tocqueville, who concluded that the United States was a unique nation, “proceeding along a path to which no limit can be perceived.”

Pinpointing the actual beginning of American imperialism is difficult. Some historians suggest that it began with the writing of the Constitution; historian Donald W. Meinig argues that the imperial behavior of the United States dates back to at least the Louisiana Purchase. He describes this event as an, “aggressive encroachment of one people upon the territory of another, resulting in the subjugation of that people to alien rule.” Here, he is referring to the U.S. policies toward Native Americans, which he said were, “designed to remold them into a people more appropriately conformed to imperial desires.”

Uncle Sam teaching the world: This caricature shows Uncle Sam lecturing four children labelled “Philippines,” “Hawaii,” “Puerto Rico,” and “Cuba” in front of children holding books labeled with various U.S. states. In the background, an American Indian holds a book upside down, a Chinese boy stands at the door, and a black boy cleans a window. The blackboard reads, “The consent of the governed is a good thing in theory, but very rare in fact… the U.S. must govern its new territories with or without their consent until they can govern themselves.”

Whatever its origins, American imperialism experienced its pinnacle from the late 1800s through the years following World War II. During this “Age of Imperialism,” the United States exerted political, social, and economic control over countries such as the Philippines, Cuba, Germany, Austria, Korea, and Japan. One of the most notable examples of American imperialism in this age was the annexation of Hawaii in 1898, which allowed the United States to gain possession and control of all ports, buildings, harbors, military equipment, and public property that had formally belonged to the Government of the Hawaiian Islands. On January 17, 1893, the last monarch of the Kingdom of Hawaii, Queen Liliuokalani, was deposed in a coup d’état led largely by American citizens who were opposed to Liliuokalani’s attempt to establish a new Constitution. This action eventually resulted in Hawaii’s becoming America’s 50th state in 1959.

Opposition to Imperialism

The American Anti-Imperialist League was an organization established in the United States on June 15, 1898, to battle the American annexation of the Philippines as an insular area. The League also argued that the Spanish-American War was a war of imperialism camouflaged as a war of liberation. The anti-imperialists opposed the expansion because they believed imperialism violated the credo of republicanism, especially the need for “consent of the governed.” They did not oppose expansion on commercial, constitutional, religious, or humanitarian grounds; rather, they believed that the annexation and administration of third-world tropical areas would mean the abandonment of American ideals of self-government and isolation—ideals expressed in the U.S. Declaration of Independence, George Washington ‘s Farewell Address, and Abraham Lincoln ‘s Gettysburg Address. The Anti-Imperialist League represented an older generation and was rooted in an earlier era; they were defeated in terms of public opinion, the 1900 election, and the actions of Congress and the president because most younger Progressives who were just coming to power supported imperialism.

The Spanish-American War

The Spanish-American War was a three-month-long conflict in 1898 between Spain and the United States.

Learning Objectives

Analyze the Spanish-American War

Key Takeaways



The Spanish-American War was a conflict in 1898 between Spain and the United States. It was the result of American intervention in the ongoing Cuban War of Independence. American attacks on Spain’s Pacific possessions led to U.S. involvement in the Philippine Revolution and ultimately to the Philippine-American War.


Revolts against Spanish rule had been endemic for decades in Cuba and were closely watched by Americans. With the abolition of slavery in 1886, former slaves joined the ranks of farmers and the urban working class, many wealthy Cubans lost their property, and the number of sugar mills declined. Only companies and the most powerful plantation owners remained in business, and during this period, U.S. financial capital began flowing into the country. Although it remained Spanish territory politically, Cuba started to depend on the United States economically. Coincidentally, around the same time, Cuba saw the rise of labor movements.

Following his second deportation to Spain in 1878, revolutionary José Martí moved to the United States in 1881. There he mobilized the support of the Cuban exile community, especially in southern Florida. He aimed for a revolution and independence from Spain, but also lobbied against the U.S. annexation of Cuba, which some American and Cuban politicians desired.

By 1897–1898, American public opinion grew angrier at reports of Spanish atrocities in Cuba. After the mysterious sinking of the American battleship Maine in Havana harbor, political pressures from the Democratic Party pushed the administration of Republican President William McKinley into a war he had wished to avoid. Compromise proved impossible, resulting in the United States sending an ultimatum to Spain that demanded it immediately surrender control of Cuba, which the Spanish rejected. First Madrid, then Washington, formally declared war.

The War

Although the main issue was Cuban independence, the 10-week war was fought in both the Caribbean and the Pacific. American naval power proved decisive, allowing U.S. expeditionary forces to disembark in Cuba against a Spanish garrison already reeling from nationwide insurgent attacks and wasted by yellow fever.

The Spanish-American War was swift and decisive. During the war’s three-month duration, not a single American reverse of any importance occurred. A week after the declaration of war, Commodore George Dewey of the six-warship Asiatic Squadron (then based at Hong Kong) steamed his fleet to the Philippines. Dewey caught the entire Spanish armada at anchor in Manila Bay and destroyed it without losing an American life.

Cuban, Philippine, and American forces obtained the surrender of Santiago de Cuba and Manila as a result of their numerical superiority in most of the battles and despite the good performance of some Spanish infantry units and spirited defenses in places such as San Juan Hill. Madrid sued for peace after two obsolete Spanish squadrons were sunk in Santiago de Cuba and Manila Bay. A third more modern fleet was recalled home to protect the Spanish coasts.

The Treaty of Paris

The result of the war was the 1898 Treaty of Paris, negotiated on terms favorable to the United States. It allowed temporary American control of Cuba and indefinite colonial authority over Puerto Rico, Guam, and the Philippines following their purchase from Spain. The defeat and collapse of the Spanish Empire was a profound shock to Spain’s national psyche, and provoked a movement of thoroughgoing philosophical and artistic reevaluation of Spanish society known as the “Generation of ’98.” The victor gained several island possessions spanning the globe, which caused a rancorous new debate over the wisdom of expansionism.

Legacy of the War

“La Fatlera del Oncle Sam”: A Catalan satirical drawing, published in La Campana de Gràcia (1896), criticizing U.S. behavior regarding Cuba.

The war marked American entry into world affairs. Before the Spanish-American War, the United States was characterized by isolationism, an approach to foreign policy that asserts that a nation’s interests are best served by keeping the affairs of other countries at a distance. Since the Spanish-American War, the United States has had a significant hand in various conflicts around the world, and has entered many treaties and agreements. The Panic of 1893 was over by this point, and the United States entered a long and prosperous period of economic and population growth and technological innovation that lasted through the 1920s. The war redefined national identity, served as a solution of sorts to the social divisions plaguing the American mind, and provided a model for all future news reporting.

The war also effectively ended the Spanish Empire. Spain had been declining as an imperial power since the early nineteenth century as a result of Napoleon’s invasion. The loss of Cuba caused a national trauma because of the affinity of peninsular Spaniards with Cuba, which was seen as another province of Spain rather than as a colony. Spain retained only a handful of overseas holdings: Spanish West Africa, Spanish Guinea, Spanish Sahara, Spanish Morocco, and the Canary Islands.

Markets and Missionaries

Progressive Era evangelism included strong political, social, and economic messages, which urged adherents to improve their society.

Key Takeaways

Social GospelAmerican Missionary AssociationEvangelical

The Social Gospel Movement

The Social Gospel was a Protestant movement that was most prominent in the early twentieth-century United States and Canada. The movement applied Christian ethics to social problems, especially issues of social justice such as economic inequality, poverty, alcoholism, crime, racial tensions, slums, unclean environments, child labor, inadequate labor unions, poor schools, and the danger of war.

In the United States, prior to World War I, the Social Gospel was the religious wing of the Progressive movement, which aimed to combat injustice, suffering, and poverty in society. Denver, Colorado, was a center of Social Gospel activism. Thomas Uzzell led the Methodist People’s Tabernacle from 1885 to 1910. He established a free dispensary for medical emergencies, an employment bureau for job seekers, a summer camp for children, night schools for extended learning, and English language classes. Myron Reed of the First Congregational Church became a spokesman for labor unions on issues such as worker’s compensation. His middle-class congregation encouraged Reed to move on when he became a Socialist, and he organized a nondenominational church. Baptist minister Jim Goodhart set up an employment bureau, and provided food and lodging for tramps and hobos at the mission he ran. He became city chaplain and director of public welfare of Denver in 1918. In addition to these Protestants, Reform Jews and Catholics helped build Denver’s social welfare system in the early twentieth century.

Walter Rauschenbusch and Dwight Moody


Pastor Dwight Moody, ca.1900: Portrait of Pastor Dwight Moody: preacher, evangelist, and publisher in the Social Gospel movement.

One of the defining theologians for the Social Gospel movement was Walter Rauschenbusch, a Baptist pastor of a congregation located in Hell’s Kitchen in New York City. Rauschenbusch railed against what he regarded as the selfishness of capitalism and promoted a form of Christian Socialism that supported the creation of labor unions and cooperative economics.

While pastors such as Rauschenbusch were combining their expertise in Biblical ethics and economic studies and research to preach theological claims around the need for social reform, others such as Dwight Moody refused to preach about social issues based on personal experience. Pastor Moody’s experience led him to believe that the poor were too particular in receiving charity. Moody claimed that concentrating on social aid distracted people from the life-saving message of the Gospel.

Rauschenbusch sought to address the problems of the city with Socialist ideas that proved to be frightening to the middle classes, the primary supporters of the Social Gospel. In contrast, Moody attempted to save people from the city and was very effective in influencing middle-class Americans who were moving into the city with traditional style revivals.

The American Missionary Association

The American Missionary Association (AMA) was a Protestant-based abolitionist group founded on September 3, 1846, in Albany, New York. The main purpose of this organization was to abolish slavery, educate African Americans, advocate for racial equality, and promote Christian values. Its members and leaders were both black and white and chiefly affiliated with Congregationalist, Methodist, and Presbyterian churches.

The AMA started The American Missionary magazine, which published from 1846 through 1934. Among its efforts was the founding of antislavery churches. For instance, the abolitionist Owen Lovejoy was among the Congregational ministers of the AMA who helped plant 115 antislavery churches in Illinois before the American Civil War, aided by the strong westward migration of individuals from the East. While the AMA became notable in the United States for its work in opposition to slavery and in support of education for freed men, it also worked in missions in numerous nations overseas. The nineteenth-century missionary effort was strong in China and east Asia.


While the Social Gospel was short-lived historically, it had a lasting impact on the policies of most of the mainline denominations in the United States. Most began programs for social reform, which led to ecumenical cooperation in 1910 during the formation of the Federal Council of Churches (although cooperation regarding social issues often led to charges of Socialism). It is likely that the Social Gospel’s strong sense of leadership by the people led to women’s suffrage, and that the emphasis it placed on morality led to prohibition. Biographer Randall Woods argues that Social Gospel themes learned from childhood allowed Lyndon B. Johnson to transform social problems into moral problems. This helps explain his longtime commitment to social justice, as exemplified by the Great Society, and his commitment to racial equality. The Social Gospel explicitly inspired his foreign-policy approach of a sort of Christian internationalism and nation building.

The Open Door Policy

The Open Door Policy aimed to keep the Chinese trade market open to all countries on an equal basis.

Key Takeaways

Open Door PolicyMonroe Doctrine

The “Open Door Policy” refers to a U.S. doctrine established in the late nineteenth century and the early twentieth century, as expressed in Secretary of State John Hay’s “Open Door Note,” dated September 6, 1899, and dispatched to the major European powers. The policy proposed to keep China open to trade with all countries on an equal basis, keeping any one power from total control of the country, and calling upon all powers, within their spheres of influence, to refrain from interfering with any treaty port or any vested interest, to permit Chinese authorities to collect tariffs on an equal basis, and to show no favors to their own nationals in the matter of harbor dues or railroad charges.

The Open Door policy was rooted in the desire of U.S. businesses to trade with Chinese markets, though the policy’s pledging to protect China’s sovereignty and territorial integrity from partition also tapped the deep-seated sympathies of those who opposed imperialism. In practice, the policy had little legal standing; it was mainly used to mediate competing interests of the colonial powers without much meaningful input from the Chinese, which created lingering resentment and caused it to be seen later as a symbol of national humiliation by many Chinese historians.

Formation of the Policy

During the First Sino-Japanese War in 1895, China faced an imminent threat of being partitioned and colonized by imperialist powers such as Britain, France, Russia, Japan, and Germany. After winning the Spanish-American War of 1898, and with the newly acquired territory of the Philippine Islands, the United States increased its Asian presence and was expecting to further its commercial and political interest in China. The United States felt threatened by other powers’ much larger spheres of influence in China and worried that it might lose access to the Chinese market should the country be partitioned.

As a response, William Woodville Rockhill formulated the Open Door Policy to safeguard American business opportunities and other interests in China. On September 6, 1899, U.S. Secretary of State John Hay sent notes to the major powers (France, Germany, Britain, Italy, Japan, and Russia), asking them to declare formally that they would uphold Chinese territorial and administrative integrity and would not interfere with the free use of the treaty ports within their spheres of influence in China. The Open Door Policy stated that all nations, including the United States, could enjoy equal access to the Chinese market.

In reply, each country tried to evade Hay’s request, taking the position that it could not commit itself until the other nations had complied. However, by July 1900, Hay announced that each of the powers had granted consent in principle. Although treaties made after 1900 refer to the Open Door Policy, competition among the various powers for special concessions within China for railroad rights, mining rights, loans, foreign trade ports, and so forth, continued unabated.

The Monroe Doctrine

The Monroe Doctrine was a U.S. foreign policy regarding domination of the Americas in 1823. It stated that further efforts by European nations to colonize land or interfere with states in North or South America would be viewed as acts of aggression, requiring U.S. intervention. At the same time, the doctrine noted that the United States would neither interfere with existing European colonies nor meddle in the internal concerns of European countries. The Doctrine was issued in 1823 at a time when nearly all Latin American colonies of Spain and Portugal had achieved, or were at the point of gaining, independence from the Portuguese and Spanish Empires.

Monroe Doctrine: A 1912 newspaper cartoon about the Monroe Doctrine.

President James Monroe first stated the doctrine during his seventh-annual State of the Union Address to Congress. The term “Monroe Doctrine” itself was coined in 1850. By the end of the nineteenth century, Monroe’s declaration was seen as a defining moment in the foreign policy of the United States and one of its longest-standing tenets. It would be invoked by many U.S. statesmen and several U.S. presidents, including Ulysses S. Grant, Theodore Roosevelt, John F. Kennedy, Ronald Reagan, and many others.

The intent and impact of the Monroe Doctrine persisted with only minor variations for more than a century. Its stated objective was to free the newly independent colonies of Latin America from European intervention and avoid situations that could make the New World a battleground for the Old World powers, so that the United States could exert its own influence undisturbed. The doctrine asserted that the New World and the Old World were to remain distinctly separate spheres of influence, for they were composed of entirely separate and independent nations.

Inherent in the Monroe Doctrine are the themes of American exceptionalism and Manifest Destiny, two ideas that refer to the right of the United States to exert its influence over the rest of the world. Under these conditions, the Monroe Doctrine was used to justify American intervention abroad multiple times throughout the nineteenth century, most notably in the Spanish-American War and with the annexation of Hawaii.

The Philippine-American War

The Philippine-American War was an armed conflict that resulted in American colonial rule of the Philippines until 1946.

Key Takeaways

Philippine Revolution of 1896Battle of ManilaAmerican Anti-Imperialist League

The Philippine-American War, also known as the “Philippine War of Independence” or the “Philippine Insurrection” (1899–1902), was an armed conflict between the United States and Filipino revolutionaries. The conflict arose after the Philippine Revolution of 1896, from the First Philippine Republic’s struggle to gain independence following annexation by the United States.

The conflict arose when the First Philippine Republic objected to the terms of the Treaty of Paris, under which the United States took possession of the Philippines from Spain after the Spanish-American War.


The Battle of Manila: The Battle of Manila, February 1899.

Fighting erupted between U.S. and Filipino revolutionary forces on February 4, 1899, and quickly escalated into the 1899 Battle of Manila. On June 2, 1899, the First Philippine Republic officially declared war against the United States. The war officially ended on July 2, 1902, with a victory for the United States. However, some Philippine groups led by veterans of the Katipunan continued to battle the American forces. Among those leaders was General Macario Sakay, a veteran Katipunan member who assumed the presidency of the proclaimed “Tagalog Republic,” formed in 1902 after the capture of President Emilio Aguinaldo. Other groups, including the Moro people and Pulahanes people, continued hostilities in remote areas and islands until their final defeat a decade later at the Battle of Bud Bagsak on June 15, 1913.

Filipino soldiers: Filipino soldiers outside Manila in 1899.

The war with and occupation by the United States would change the cultural landscape of the islands. The war resulted in an estimated 34,000 to 220,000 Philippine casualties (with more civilians dying from disease and hunger brought about by war); the disestablishment of the Roman Catholic Church as the state religion; and the introduction of the English language in the islands as the primary language of government, education, business, and industry, and increasingly in future decades, of families and educated individuals.

Under the 1902 “Philippine Organic Act,” passed by the U.S. Congress, Filipinos initially were given very limited self-government, including the right to vote for some elected officials such as a Philippine Assembly. But it was not until 14 years later, with the passage of the 1916 Philippine Autonomy Act (or “Jones Act”), that the United States officially promised eventual independence, along with more Philippine control in the meantime over the Philippines. The 1934 Philippine Independence Act created in the following year the Commonwealth of the Philippines, a limited form of independence, and established a process ending in Philippine independence (originally scheduled for 1944, but interrupted and delayed by World War II). Finally in 1946, following World War II and the Japanese occupation of the Philippines, the United States granted independence through the Treaty of Manila.

American Opposition

Some Americans, notably William Jennings Bryan, Mark Twain, Andrew Carnegie, Ernest Crosby, and other members of the American Anti-Imperialist League, strongly objected to the annexation of the Philippines. Anti-imperialist movements claimed that the United States had become a colonial power by replacing Spain as the colonial power in the Philippines. Other anti-imperialists opposed annexation on racist grounds. Among these was Senator Benjamin Tillman of South Carolina, who feared that annexation of the Philippines would lead to an influx of nonwhite immigrants into the United States. As news of atrocities committed in subduing the Philippines arrived in the United States, support for the war flagged.

The Banana Wars

The Banana Wars were a series of U.S. military occupations and interventions in Latin American and Caribbean countries during the early 1900s.

Key Takeaways

Roosevelt CorollaryUnited Fruit Company

The Banana Wars, also known as the “American-Caribbean Wars,” were a series of occupations, police actions, and interventions involving the United States in Central America and the Caribbean. This period of conflict started with the Spanish-American War in 1898 and the subsequent Treaty of Paris, which gave the United States control of Cuba and Puerto Rico. Thereafter, the United States conducted military interventions in Cuba, Panama, Honduras, Nicaragua, Mexico, Haiti, and the Dominican Republic. The series of conflicts ended with the withdrawal of troops from Haiti in 1934 under President Franklin D. Roosevelt. Reasons for these conflicts were varied but were largely economic in nature. The conflict was called the “Banana Wars” because of the connections between U.S. interventions and the preservation of American commercial interests in the region.

United Fruit Company Steamship Service: A 1916 advertisement for the United Fruit Company Steamship Service.

Most prominently, the United Fruit Company had significant financial stakes in the production of bananas, tobacco, sugar cane, and various other products throughout the Caribbean, Central America, and northern South America. The United States also was advancing its political interests, maintaining a sphere of influence and controlling the Panama Canal, which it had recently built and which was critically important to global trade and naval power.

Panama and the Canal

In 1882, Ferdinand de Lesseps started work on a canal, but by 1889, the effort had experienced engineering challenges caused by frequent landslides, slippage of equipment, and mud, and resulted in bankruptcy. U.S. President Theodore Roosevelt convinced Congress to take on the abandoned works in 1902, while Colombia was in the midst of the Thousand Days’ War. During the war, Panamanian Liberals made at least three attempts to seize control of Panama and potentially achieve full autonomy. Liberal guerrillas such as Belisario Porras and Victoriano Lorenzo were suppressed by a collaboration between conservative Colombian and U.S. forces under the Mallarino-Bidlack Treaty. The Roosevelt administration proposed to Colombia that the United States should control the canal, but by mid-1903, the Colombian government refused. The United States then changed tactics.

Less than three weeks later, on November 18, 1903, the Hay-Bunau-Varilla Treaty was signed between Frenchman Philippe-Jean Bunau-Varilla, who had promptly been appointed Panamanian ambassador to the United States (representing Panamanian interests), and the U.S. Secretary of State John Hay. The treaty allowed for the construction of a canal and U.S. sovereignty over a strip of land 10-miles wide and 50-miles long on either side of the Panama Canal Zone. In that zone, the United States would build a canal, then administer, fortify, and defend it “in perpetuity.”

Honduras and American Fruit Companies

Honduras, where the United Fruit Company and Standard Fruit Company dominated the country’s key banana export sector and associated land holdings and railways, saw the insertion of American troops in 1903, 1907, 1911, 1912, 1919, 1924, and 1925. The writer O. Henry coined the term “banana republic” in 1904 to describe Honduras.

The first decades of Honduras’s history were marked by instability in terms of politics and economy. Indeed, the political context gave way to 210 armed conflicts between independence and the rise to power of the Carias government. This instability was due in part to American involvement in the country.

The first company that concluded an agreement with the Honduras government was the Vaccaro Brothers Company (Standard Fruit Company). The Cuyamel Fruit Company then followed that lead. The United Fruit Company also agreed to a contract with the government, which was attained through its subsidies (the Tela Rail Road Company and Truxillo Rail Road Company).

Different avenues led to the signature of a contract between the Honduras government and the American companies. The most popular avenue was to obtain a grab on a piece of land in exchange for the completion of railroads in Honduras; this explains why a railroad company conducted the agreement between the United Fruit Company and Honduras. The ultimate goal in the acquisition of a contract was to control the bananas, from production to distribution. Therefore, the American companies would finance guerrilla fighters, presidential campaigns, and governments.


The U.S. military involvements with Mexico in this period are related to the same general commercial and political causes, but stand as a special case. The Americans conducted the Border War with Mexico from 1910 to 1919 for additional reasons: to control the flow of immigrants and refugees from revolutionary Mexico (pacificos), and to counter rebel raids into U.S. territory. The 1914 U.S. occupation of Veracruz, however, was an exercise of armed influence, not an issue of border integrity; it was aimed at cutting off the supplies of German munitions to the government of Mexican leader Victoriano Huerta, whom U.S. President Woodrow Wilson refused to recognize. In the years prior to World War I, the United States also was sensitive to the regional balance of power against Germany. The Germans were actively arming and advising the Mexicans, as demonstrated by the 1914 SS Ypiranga arms-shipping incident, the establishment of German saboteur Lothar Witzke’s base in Mexico City, the 1917 Zimmermann Telegram, and the presence of German advisors during the 1918 Battle of Ambos Nogales. Only twice during the Mexican Revolution did the U.S. military occupy Mexico: during the temporary occupation of Veracruz in 1914 and between the years 1916 and 1917, when U.S. General John Pershing and his army came to Mexico to lead a nationwide search for Pancho Villa.

Other Countries

Other Latin American nations were influenced or dominated by American economic policies and/or commercial interests to the point of coercion. Theodore Roosevelt declared the Roosevelt Corollary to the Monroe Doctrine in 1904, asserting the right of the United States to intervene to stabilize the economic affairs of states in the Caribbean and Central America if they were unable to pay their international debts. From 1909 to 1913, President William Howard Taft and his Secretary of State Philander C. Knox asserted a more “peaceful and economic” Dollar Diplomacy foreign policy, although that, too, was backed by force. The U.S. Marine Corps most often carried out these military interventions. The Marines were called in so often that they developed a Small Wars Manual, The Strategy and Tactics of Small Wars, in 1921. On occasion, U.S. Naval gunfire and U.S. Army troops were also used.