Manifest Destiny: Continental Expansion and the Seeds of Empire

Name: Louisiana Purchase
Start: 1803
Location: Mississippi River to the Rocky Mountains

Jeff Kellick
Jan 11
23 min read

Updated: May 1

I more than suspect already, that he is deeply conscious of being in the wrong—that he feels the blood of this war, like the blood of Abel, is crying to Heaven against him.—Abraham Lincoln on President Polk, 1848²

The Phrase We Never Examine

“Manifest Destiny” is one of those phrases Americans absorb without examining. It sounds like natural growth, inevitable progress—the continent filling in like water finding its level. The words suggest that American expansion from the Atlantic to the Pacific was not a choice but a fate, not a policy but a prophecy. The very phrase discourages critical thought: if something is destined, what is there to debate?

The term itself was coined in 1845 by journalist John L. O’Sullivan, who wrote that it was “our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions.”¹ Note the passive construction: destiny manifests itself; America does not choose but fulfills. Note the theological framing: Providence allots; expansion is divine will, not human ambition. The phrase was propaganda from its first utterance—a rhetorical device designed to foreclose debate by presenting policy as prophecy.

However, let us consider: continental expansion involved choices, and those choices were contested. Some expansions were peaceful purchases; others were wars of conquest. Some respected existing populations, however imperfectly; others dispossessed them with calculated brutality. The distinction matters because the habits of thought formed during continental expansion—the rationalizations, the manufactured crises, the executive manipulations—shaped the turn to overseas empire that would come in 1898.

This article examines that range of experience. From Jefferson’s Louisiana Purchase to Polk’s Mexican War to Cleveland’s refusal to annex Hawaii, we trace how Americans debated expansion in their own time. We will find that principled opposition existed—that the path to empire was contested at every juncture. We will also find, uncomfortably, that practices of conquest and dispossession within the continent established templates that would later be applied abroad. The Mexican-American War in particular created a playbook—executive provocation, manufactured casus belli, congressional acquiescence, critics marginalized as unpatriotic—that would be used again and again, from the Maine to the Gulf of Tonkin to the weapons of mass destruction to narco-terrorism.

Continental expansion was not monolithic. Understanding its variations—and the debates it generated—is essential to understanding how America later chose overseas empire.

The Louisiana Purchase: Expansion Without Conquest

In 1803, Thomas Jefferson doubled the size of the United States without firing a shot.

The Louisiana Purchase remains the most consequential real estate transaction in history. For approximately $15 million—roughly four cents per acre—the United States acquired 828,000 square miles of territory stretching from the Mississippi River to the Rocky Mountains.³ The acquisition was made possible by Napoleon’s strategic calculation that he could not defend the territory against British naval power, and by Jefferson’s willingness to seize an unexpected opportunity.

But Jefferson was troubled. He believed, correctly, that the Constitution did not explicitly authorize the federal government to acquire foreign territory.⁴ He drafted a constitutional amendment to provide authorization, then abandoned the effort when he learned Napoleon might withdraw the offer. Jefferson, the strict constructionist, chose pragmatism over principle.

The constitutional question matters for our purposes. Jefferson’s decision established a precedent: executive action in foreign affairs could expand beyond strict constitutional warrant when opportunity presented itself. The republic would not be destroyed by the Louisiana Purchase—indeed, it was enormously strengthened. But the precedent of constitutional flexibility in territorial matters would later be invoked for less benign purposes.

What the Louisiana Purchase was not is equally important. It was not conquest—the territory was purchased from a European power with nominal claim, not seized from inhabitants by force. It was not colonization in the European imperial sense—the acquired territory would be organized into states equal to the original thirteen, not held as permanent dependencies. It was not, in the language of the founders, “foreign entanglement”—the transaction created no alliance, no ongoing obligation, no commitment to defend French interests.

The Louisiana model—peaceful acquisition through purchase, with territory to be organized into equal states—would be repeated with Florida (1819), the Gadsden Purchase (1853), and Alaska (1867). This model was consistent with republican principles. The problem was that peaceful acquisition was not the only model available. Another model existed, one involving war, conquest, and dispossession. That model would increasingly dominate.

The Indian Wars: Domestic Empire

Any honest account of continental expansion must confront an uncomfortable truth: the American West was not empty. Expansion required dispossession, and dispossession was accomplished through sustained violence over more than a century.

But before examining that violence, we must dispel a simplification that distorts understanding: there was no monolithic “Indian” nation. The indigenous peoples of North America comprised hundreds of distinct nations, each with its own language, culture, political structure, territory, and interests. The Iroquois Confederacy of the Northeast operated a sophisticated constitutional system that some scholars argue influenced the American founders. The Cherokee of the Southeast had adopted written language, Christianity, plantation agriculture, and republican government—earning the condescending label “Civilized Tribes” from Americans who would nonetheless dispossess them. The Comanche dominated the Southern Plains as a mounted warrior empire that held off Spanish, Mexican, and American expansion for generations. The Navajo were pastoralists; the Pueblo peoples were settled agriculturalists in ancient cities. The Pacific Northwest tribes built elaborate societies around salmon fishing; the Great Basin peoples adapted to harsh desert conditions through mobile foraging.

These nations had their own histories, their own conflicts, their own ambitions. Long before European contact, tribes warred against each other, formed alliances, competed for territory and resources. The arrival of Europeans added new players to existing dynamics—it did not create conflict where none existed. Understanding this complexity is essential because American policy toward Native peoples was never uniform. It varied by tribe, by region, by era, and by circumstance.

The Colonial and Revolutionary Period

During the colonial period and the Revolution, Native nations were sovereign powers whose alliances mattered. The Iroquois Confederacy—the Haudenosaunee—balanced between British and French interests for decades, extracting concessions from both. When the Revolution came, the Confederacy split: the Oneida and Tuscarora sided with the Americans; the Mohawk, Seneca, Onondaga, and Cayuga largely supported Britain. This was not irrational—the British had attempted to limit colonial expansion westward with the Proclamation of 1763, while American settlers pushed relentlessly onto Native lands.

The Revolution’s aftermath was catastrophic for Native peoples regardless of which side they had chosen. American victory brought American settlers, and the new federal government lacked either the will or the capacity to restrain them. Treaties were signed and broken. The pattern was established early: the United States would negotiate as with sovereign nations, then disregard those negotiations when convenient.

The “Civilization” Policy

In the early republic, federal policy oscillated between competing approaches. One strand, associated with figures like Henry Knox (Washington’s Secretary of War) and later Thomas Jefferson, advocated “civilization”—the idea that Native peoples could be assimilated into American society if they adopted European agricultural practices, Christianity, and political organization. This policy was paternalistic and ultimately coercive, but it at least acknowledged Native peoples as potentially equal participants in American life.

The “Five Civilized Tribes” of the Southeast—the Cherokee, Chickasaw, Choctaw, Creek, and Seminole—pursued this path with remarkable success. The Cherokee developed a written syllabary, published newspapers, adopted a written constitution modeled on the American document, practiced plantation agriculture, and in some cases owned African American slaves. By the standards Americans themselves had set, the Cherokee had “civilized.” It made no difference.

Jackson and Removal

Andrew Jackson’s presidency (1829-1837) marked a decisive turn. Jackson had made his military reputation fighting the Creek and Seminole; he harbored no sympathy for accommodation. The Indian Removal Act of 1830 authorized the forced relocation of southeastern tribes to territory west of the Mississippi—land then considered worthless, beyond the pale of American settlement.⁶

The justification was explicitly racial. Jackson argued that Native peoples were incapable of civilization, that their presence impeded American progress, and that removal was actually benevolent—it would protect them from extinction by separating them from white settlers. The argument was self-serving nonsense: the Cherokee had demonstrably “civilized” by every metric Jackson claimed to value, and removal would prove anything but protective.

The Cherokee Nation challenged the policy in federal court. In *Cherokee Nation v. Georgia* (1831), Chief Justice John Marshall ruled that tribes were “domestic dependent nations”—a novel category that acknowledged their sovereignty while subordinating it to federal authority. In *Worcester v. Georgia* (1832), Marshall went further, ruling that Georgia had no authority over Cherokee lands and that federal treaty obligations must be respected.⁷ The decision was a ringing affirmation of tribal sovereignty and federal treaty obligations.

Jackson reportedly responded: “John Marshall has made his decision; now let him enforce it.”⁸

Whether or not Jackson spoke those exact words, his administration proceeded with removal. The Cherokee, along with the Creek, Seminole, Chickasaw, and Choctaw nations, were forced westward on what became known as the Trail of Tears. Estimates of deaths during the Cherokee removal alone range from 4,000 to 8,000—roughly one-quarter of the relocated population.⁹

The Seminole resisted. The Second Seminole War (1835-1842) became the longest and most expensive Indian war in American history, costing thousands of lives and tens of millions of dollars. Many Seminole were eventually removed, but a remnant remained in the Florida Everglades, never conquered, never surrendering—their descendants remain there today.

The Plains Wars

West of the Mississippi, a different dynamic prevailed. The Plains tribes—the Sioux, Cheyenne, Arapaho, Comanche, Kiowa, and others—were mobile, mounted warriors whose military capabilities posed genuine threats to American expansion. The Comanche in particular had built what historian Pekka Hämäläinen calls an “empire”—a dominant power that controlled the Southern Plains, raided deep into Mexico, and successfully resisted Spanish, Mexican, and American encroachment for generations.

American policy toward the Plains tribes combined treaty-making, military campaigns, and deliberate destruction of the buffalo herds that sustained Plains life. The strategy was explicit: destroy the buffalo, and the “Indian problem” would solve itself. General Philip Sheridan allegedly remarked that buffalo hunters “have done more to settle the vexed Indian question than the entire regular army has done in the last forty years.” The buffalo population collapsed from tens of millions to near extinction by the 1880s. The Plains tribes, their economic base destroyed, had no choice but submission.

The wars were brutal on both sides. The Sand Creek Massacre (1864) saw Colorado militia slaughter a peaceful Cheyenne and Arapaho encampment, killing women, children, and elders, mutilating bodies. The Fetterman Fight (1866) saw Lakota, Cheyenne, and Arapaho warriors annihilate an American cavalry detachment. Little Bighorn (1876) became the most famous Indian victory—and guaranteed savage American retaliation. Wounded Knee (1890), where American troops massacred several hundred Lakota, including many women and children, marked the symbolic end of armed resistance.

Varying Policies, Consistent Outcome

American policy was never monolithic. At various times, the federal government pursued “civilization,” removal, reservation confinement, assimilation (including forced boarding schools designed to “kill the Indian, save the man”), and allotment (breaking up communal tribal lands into individual parcels that could then be sold to white settlers). Each policy was presented as reform; each resulted in further dispossession.

Some tribes allied with the United States against traditional Native enemies and found their loyalty unrewarded. The Crow and Pawnee scouted for the Army against the Sioux—and ended up on reservations nonetheless. The Cherokee had fought alongside Andrew Jackson against the Creek—and Jackson repaid them with removal. Alliances with the United States proved worthless; the outcome was the same regardless of tribal policy.

The Libertarian Assessment

The Indian Wars—a term that obscures as much as it reveals—were wars of conquest. They involved military campaigns, forced relocations, broken treaties, and deliberate destruction of indigenous ways of life. The death toll is impossible to calculate precisely, but scholars estimate that the Native American population of what became the United States declined from several million at contact to approximately 250,000 by 1900.⁵ This was demographic catastrophe, accomplished through disease, warfare, and systematic displacement.

A libertarian analysis cannot sanitize this history. The dispossession of Native Americans violated the natural rights principles that libertarianism claims to uphold. If individuals have rights to life, liberty, and property—and libertarian philosophy insists they do—then those rights applied to the indigenous peoples who inhabited the continent, regardless of their cultural practices or political organization. The treaties that were made and broken, the lands that were seized, the populations that were forcibly relocated—these were violations of natural rights by any consistent standard.

The complexity of tribal politics does not excuse American conduct. That the Sioux and Crow were traditional enemies does not justify dispossessing both. That some tribes practiced slavery or warfare does not justify the destruction of all. The logic that holds criminals responsible for their individual acts, not their ethnic group, applies equally to Native peoples. American policy treated “Indians” as a collective problem to be solved, not as individuals and nations with rights to be respected.

The Imperial Template

The relevance for our series is this: if America practiced conquest and subjugation domestically, the turn to overseas empire was not a complete departure but an extension of existing practice to new territories and new peoples. The habits of imperial thinking—that some peoples were not capable of self-government, that their lands were better utilized by “civilization,” that treaties with them could be broken when convenient—were formed at home before they were applied abroad.

When American troops fought Filipino independence fighters in 1899, they employed tactics developed against the Sioux and Apache. When American administrators established colonial governments in Puerto Rico and the Philippines, they drew on experience managing Indian reservations. When American generals spoke of Filipino “insurgents” as savages requiring firm handling, they echoed decades of rhetoric about Native peoples. The personnel overlapped: officers who had fought in the Indian Wars led the Philippine campaigns. The ideology was continuous.

This is domestic empire: conquest and subjugation within claimed territorial boundaries, conducted over generations, rationalized by theories of racial superiority and civilizational progress. The founders spoke eloquently of liberty, but their vision did not extend to the continent’s original inhabitants. This failure haunts the American project—and it established patterns that would shape American conduct when the republic turned its attention overseas.

The Mexican-American War: The Template for Imperial War

If the Louisiana Purchase represented expansion consistent with republican principles, the Mexican-American War of 1846-1848 represented something different: a war of conquest, provoked by executive manipulation, opposed by principled voices, and justified by claims that would be repeated for the next 175 years.

James K. Polk won the 1844 election on an openly expansionist platform. He sought California, New Mexico, and the disputed territory between the Nueces River and the Rio Grande. Mexico refused to sell. Polk determined to take by force what could not be obtained by negotiation.

The constitutional problem was that only Congress can declare war. Polk needed a casus belli—an incident that would justify military action. He manufactured one.

In January 1846, Polk ordered General Zachary Taylor to march troops into the disputed territory between the Nueces and Rio Grande—land that Mexico considered its own.¹⁰ When Mexican forces attacked Taylor’s detachment in April, Polk had his incident. On May 11, 1846, he sent a war message to Congress declaring that Mexico had “shed American blood upon the American soil.”¹¹

This was, at best, a distortion. The territory where blood was shed was disputed; Mexico had a colorable claim to it. Polk had deliberately placed American troops in harm’s way, in territory Mexico considered its own, precisely to provoke the incident he then used to justify war.

Not all Americans accepted the narrative.

The Whig Opposition

The Whig Party opposed the war as executive usurpation and territorial conquest. Their opposition was not pacifist—many Whigs supported military action once war was declared—but they refused to accept Polk’s framing. The war, they argued, was an aggressive conflict designed to seize territory and extend slavery, initiated through presidential manipulation of the facts.

The opposition included some of the most distinguished names in American politics. Daniel Webster denounced the war’s origins. Henry Clay, the Whig leader, opposed it. John Quincy Adams, the aging former president still serving in the House, voted against the war appropriations and called Polk’s claims “the most lamentable and most deplorable” deception.

No Whig articulated this critique more sharply than a first-term congressman from Illinois named Abraham Lincoln.

Lincoln introduced his famous “Spot Resolutions” on December 22, 1847, demanding that Polk identify “the particular spot of soil on which the blood of our citizens was so shed.”² Lincoln’s point was devastating: if the soil was genuinely American, Polk should be able to identify it; if he could not, his entire justification for war collapsed.

Lincoln continued his attack in a speech on January 12, 1848:

I more than suspect already, that he is deeply conscious of being in the wrong—that he feels the blood of this war, like the blood of Abel, is crying to Heaven against him. That originally having some strong motive... to involve the two countries in a war, and trusting to escape scrutiny, by fixing the public gaze upon the exceeding brightness of military glory... he plunged into it, and has swept, on and on, till, disappointed in his calculation of the ease with which Mexico might be subdued, he now finds himself, he knows not where.²

The critique cost Lincoln politically—he was labeled unpatriotic and “Spotty Lincoln” by his opponents—and did not seek reelection. But his analysis proved prescient. The Mexican-American War was exactly what he said: an aggressive war manufactured by a president who deceived Congress about the circumstances and swept the nation into conflict before deliberation could occur.

The opposition extended beyond the Whigs. Henry David Thoreau refused to pay his poll tax in protest against the war and slavery’s extension, spending a night in jail and later writing his famous essay “Civil Disobedience” to explain his reasoning. The abolitionist press condemned the war as a slaveholder’s conspiracy. In New England, opposition was so intense that some suggested secession.

Yet the war proceeded. Military victories generated patriotic fervor that drowned out critics. The pattern was established: principled opposition existed, was articulated, and was swept aside by war fever.

The Consequences

The United States won the military contest decisively. The Treaty of Guadalupe Hidalgo (1848) transferred to the United States approximately 525,000 square miles of territory—present-day California, Nevada, Utah, and Arizona, along with parts of New Mexico, Colorado, and Wyoming.¹² The acquisition transformed America into a continental power stretching from Atlantic to Pacific.

But consequences followed. The Wilmot Proviso debate—whether slavery would be permitted in the conquered territories—accelerated the sectional crisis that would produce Civil War thirteen years later.¹³ Ulysses Grant, who served as a young officer in Mexico, later offered this judgment in his memoirs: “I do not think there was ever a more wicked war than that waged by the United States on Mexico. I thought so at the time, when I was a youngster, only I had not moral courage enough to resign.”¹⁴ In his later reflection, Grant called it “one of the most unjust ever waged by a stronger against a weaker nation.”¹⁴

The Template Established

The Mexican-American War established a template that would recur throughout American history:

Executive manipulation: A president determined on war creates circumstances designed to produce an incident, then presents Congress with a fait accompli.
Manufactured causus belli: The triggering incident is presented as foreign aggression against America, when it was actually American provocation on disputed or foreign territory.
Congressional acquiescence: Congress votes for war after the fact, unwilling to deny support to troops already in the field.
Critics marginalized: Those who question the war’s legitimacy are labeled unpatriotic, disloyal, or cowardly. Their arguments are not answered; they are shouted down.
Long-term consequences unforeseen: The war’s architects do not anticipate how territorial conquest will destabilize domestic politics.

This template would be applied again and again: the Maine (1898), the Lusitania (contributing to 1917 entry), the Gulf of Tonkin (1964), weapons of mass destruction (2003). Each time, the pattern repeated: a triggering incident, presidential framing, congressional acquiescence, critics silenced, consequences unexamined until too late.

lolThe Civil War was not a foreign policy war in the sense that concerns this series. It was an existential domestic conflict over the nature of the union and the future of slavery. A full treatment is beyond our scope with this series.

Two points are relevant.

First, the Civil War demonstrated that even existential conflict need not produce foreign entanglement. Lincoln’s administration successfully prevented European recognition of the Confederacy, managing the delicate diplomacy of the Trent Affair (1861) without stumbling into war with Britain.¹⁵ The Union maintained the founders’ principles regarding foreign involvement even during its greatest crisis.

Second, the war’s effects on federal power and the standing military would prove significant for later developments. The Civil War created a large professional military, accumulated enormous federal debt, expanded executive authority dramatically, and established precedents for wartime restrictions on civil liberties. These developments were arguably necessary to preserve the union—but they created institutional capacities that would later be applied to overseas empire.

Post-Civil War Restraint

After Appomattox, imperial temptation arose—and was resisted.

President Ulysses Grant sought to annex Santo Domingo (the Dominican Republic) in 1870. His motives were mixed: strategic interest in Caribbean bases, concern for the welfare of freedpeople who might emigrate, and perhaps personal financial interests of his associates. Grant submitted an annexation treaty to the Senate.¹⁶

The treaty failed. Senator Charles Sumner of Massachusetts led the opposition, arguing that annexation violated the rights of the Dominican people to self-determination.¹⁷ The Senate rejected the treaty 28-28, falling short of the required two-thirds majority.

The episode is significant because it shows the republic still possessed institutional antibodies against territorial expansion beyond the continent. Grant was a popular president and war hero. He pushed hard for annexation. And he lost. The distinction between continental consolidation and overseas empire still commanded respect.

The quarter-century from 1865 to 1890 was relatively quiet on the imperial front. America focused on Reconstruction, then industrialization. The Alaska Purchase (1867) continued the model of peaceful acquisition.¹⁸ The Indian Wars continued their grim progress on the continent, but overseas imperialism remained off the national agenda.

This relative quiet would not last. Forces were gathering—ideological, economic, strategic—that would push America toward a different path. But before examining those forces, we must consider the last president to apply the founders’ foreign policy principles: Grover Cleveland.

Grover Cleveland: The Last Anti-Imperialist President

Grover Cleveland was not a radical. He was a conservative Democrat, a proponent of sound money, limited government, and strict constitutional construction. He was the only president until Donald Trump to serve two non-consecutive terms, winning in 1884, losing in 1888, and winning again in 1892. His anti-imperialism was not ideological eccentricity but mainstream Democratic principle—the same tradition that had animated Jefferson and Madison.

Cleveland’s commitment to limited government was consistent. He vetoed more bills than all previous presidents combined, including numerous private pension bills he considered raids on the treasury. He resisted protective tariffs. He opposed federal intervention in the economy beyond constitutional warrant. His foreign policy was of a piece with his domestic philosophy: the United States should not project power where it had no legitimate interest, should not acquire territory through force or fraud, and should not interfere in other nations’ internal affairs.

Cleveland’s test came over Hawaii.

American sugar planters and missionaries had established significant economic and cultural presence in Hawaii by the 1890s. They chafed under the rule of Queen Liliuokalani, who sought to strengthen native Hawaiian governance at the expense of American influence. In January 1893, with the connivance of the American minister to Hawaii, John L. Stevens, and the support of U.S. Marines landed from the USS Boston, American residents overthrew the queen and established a provisional government.¹⁹

The Harrison administration, in its final weeks, negotiated an annexation treaty and submitted it to the Senate. Then Cleveland took office.

Cleveland withdrew the treaty and ordered an investigation. His commissioner, James Blount, reported that the revolution had been accomplished by American force, that most native Hawaiians opposed annexation, and that the overthrow would not have succeeded without the Marines’ presence.²⁰ Minister Stevens had actively conspired with the revolutionaries and had recognized the provisional government before the queen had formally surrendered—effectively using American military force to accomplish regime change.

Cleveland’s conclusion was unambiguous: the United States had participated in the illegitimate overthrow of a sovereign government. He refused to complete the annexation of territory “seized by fraud and force.”

In his message to Congress, Cleveland laid out his reasoning with clarity that echoes across the generations:

I mistake the American people if they favor the odious doctrine that there is no such thing as international morality, that there is one law for a strong nation and another for a weak one, and that even by indirection a strong power may with impunity despoil a weak one of its territory.²¹

Cleveland considered attempting to restore the queen—a proposal that proved impractical given the provisional government’s entrenchment and its possession of arms. Unable to undo the wrong, he refused to ratify it. Hawaii remained in limbo, governed by the Republic of Hawaii proclaimed by the American settlers, unannexed by the United States.

This was the founders’ foreign policy applied to a concrete case. America should not acquire territory through conquest or subterfuge. Cleveland’s principles commanded enough support that annexation remained blocked through the remainder of his term.

He was the last president to hold that line. Hawaii would be annexed in 1898, under President McKinley, during the war fever of the Spanish-American conflict—justified not on moral grounds but on strategic necessity for Pacific bases. Cleveland lived until 1908—long enough to see America become an imperial power with colonies across the Pacific, fighting a brutal counterinsurgency in the Philippines, exactly the kind of entanglement the founders warned against. He opposed it to the end.

The Gathering Storm

By the 1890s, forces were converging that would overwhelm the anti-imperialist tradition Cleveland represented.

Ideological forces: Social Darwinism applied “survival of the fittest” to nations, arguing that expansion was not merely permissible but biological necessity.²³ The strong must dominate the weak; this was nature’s law. Anglo-Saxonism and racial theories of civilization provided pseudo-scientific justification for expansion, arguing that the “Anglo-Saxon race” had a special genius for self-government and a duty to spread it—by force if necessary. The “white man’s burden,” articulated most famously by Rudyard Kipling in his poem urging American conquest of the Philippines, framed imperial conquest as moral obligation rather than naked aggression. Josiah Strong’s influential book *Our Country* (1885) combined Protestant millennialism with Anglo-Saxon racism, arguing that God had prepared the Anglo-Saxon race to spread Christian civilization across the globe, and that America was the chosen instrument of this divine purpose.²² The book sold hundreds of thousands of copies.
Strategic forces: Alfred Thayer Mahan’s *The Influence of Sea Power Upon History* (1890) transformed American strategic thinking.²⁴ Mahan argued that national greatness required naval power, and naval power required overseas bases for coaling stations, repairs, and resupply. A navy that could not refuel across the Pacific or Caribbean was a navy limited to coastal defense. Strategic logic demanded Pacific and Caribbean possessions—Hawaii, the Philippines, Cuba, Puerto Rico.

The United States began building a modern steel navy in the 1880s. By the 1890s, America had the fifth-largest navy in the world and strategic theorists were asking what it was for. The answer increasingly pointed toward overseas power projection.
Economic forces: American industry had grown explosively since the Civil War. By the 1890s, the United States was the world’s leading industrial power—and producers worried that the domestic market could not absorb their output. New markets were needed, or so the argument ran. The 1893 depression intensified the search for export opportunities. Asia, Latin America, the Pacific islands beckoned as markets for American manufactures and sources of raw materials.

The economic argument for empire was dubious on its merits—trade does not require conquest, and American exports would grow dramatically in the twentieth century without acquiring colonies—but it was politically powerful. Business interests that had once opposed territorial expansion as costly distraction began to see strategic possibilities.
Psychological forces: The 1890 census announced the “closing of the frontier.” The frontier had been central to American identity—the safety valve for social tensions, the crucible of American character, the physical space where democracy renewed itself. Frederick Jackson Turner’s famous 1893 address on “The Significance of the Frontier in American History” argued that American democracy and individualism were products of the frontier experience.²⁵ Its disappearance created anxiety: what would America become without new territory to conquer?

The search for new frontiers pointed outward. Cuba, Hawaii, the Philippines, China—all beckoned as arenas for American energy and ambition. The psychological need for expansion had been severed from any connection to continental consolidation.
Media forces: The yellow press of Hearst and Pulitzer discovered that war sold newspapers. William Randolph Hearst’s *New York Journal* and Joseph Pulitzer’s *New York World* competed in sensationalism, each trying to outdo the other in lurid coverage of Spanish atrocities in Cuba. Atrocities were real—Spain’s reconcentrado policy killed tens of thousands of Cuban civilians—but the press exaggerated, fabricated, and inflamed. By 1897, media drumbeats for intervention had reached fever pitch.

The apocryphal exchange between Hearst and artist Frederic Remington captures the spirit: when Remington cabled from Cuba that there was no war to illustrate, Hearst allegedly replied, “You furnish the pictures and I’ll furnish the war.” Whether the exchange occurred or not, it accurately describes the press’s role in manufacturing public demand for intervention.

Yet the anti-imperialist tradition remained alive. Cleveland’s principles still commanded respect in significant quarters. The Democratic Party’s 1896 platform opposed “territorial expansion” and the “acquisition of new territory without the consent of the people thereof.” Men of letters like William Dean Howells, Mark Twain, and William James would soon organize resistance to empire. The transformation required a catalyzing event—an incident that would sweep away restraint in a tide of patriotic fervor.

That event was coming. On February 15, 1898, in Havana Harbor, the USS Maine would explode.

Continental Lessons for Overseas Empire

What did continental expansion teach?

First, peaceful acquisition was possible but not universal. The Louisiana Purchase, Florida, Alaska—these demonstrated that expansion could occur through negotiation and purchase, without war, consistent with republican principles.
Second, wars of conquest could be manufactured. The Mexican-American War showed that a determined president could create incidents, manipulate public opinion, and stampede Congress into supporting an aggressive war.
Third, dispossession of indigenous peoples established habits of imperial thinking. The practices developed in the Indian Wars—military campaigns against peoples deemed “savages,” removal to reservations, destruction of traditional ways of life—created templates and trained personnel that would be deployed overseas.
Fourth, principled opposition existed but could be overcome by war fever. Lincoln opposed the Mexican War; Sumner blocked Dominican annexation; Cleveland refused Hawaiian conquest. But when war fever struck, as it would in 1898, such voices were drowned out.
Fifth, long-term consequences were rarely considered. Polk did not anticipate that his war would accelerate the crisis that produced Civil War. The architects of expansion did not foresee what they were building.

As of 1897, America stood at a fork in the road. The republic could consolidate its continental gains and remain what it had been—a regional power, commercially engaged with the world, politically detached from it, following the founders’ counsel. The principles articulated by Washington, Jefferson, and Madison remained viable. Cleveland had demonstrated they could still be applied.

The choice for empire was not inevitable. It was chosen—in the heat of manufactured crisis, amid the propaganda of yellow journalism, in the intoxication of military victory. Understanding how that choice was made, and what alternatives existed, requires examining the world America was about to enter: the European imperial system, the alliance structures, and the great-power rivalries that Washington warned against.

America was about to discard the founders’ wisdom and embrace the entanglements they had counseled against. The consequences would unfold across the next century and beyond—and we live with them still.

Self-Reflection Prompts

These questions are designed to help you clarify your own thinking about American expansion. There are no right or wrong answers—only more or less examined positions.

Do you distinguish between continental expansion (filling in contiguous territory) and overseas imperialism (acquiring distant colonies)? If so, what is the moral or practical difference? If not, what connects them?
Lincoln opposed the Mexican-American War as executive manipulation and territorial conquest. How does his critique apply to later American wars? Are there wars you believe fit the pattern he identified?
Cleveland refused Hawaiian annexation because the overthrow was accomplished by fraud and American force. What principle was he applying? Do you agree with it? Can you think of cases where the United States has since violated it?
The Mexican-American War contributed to the sectional crisis that produced the Civil War. Do you think expansionist policies can have unintended long-term consequences? Can you identify other examples where military action produced consequences its architects did not anticipate?
The Indian Wars are often treated separately from American foreign policy. This article argues they established templates for overseas empire. Do you find this argument persuasive? Why or why not?

Endnotes

¹ O’Sullivan, John L. “Annexation.” *United States Magazine and Democratic Review*, Vol. 17, No. 1 (July-August 1845), pp. 5-10.

² Lincoln, Abraham. Speech in the United States House of Representatives, January 12, 1848. *Congressional Globe*, 30th Congress, 1st Session, pp. 154-156. Lincoln’s Spot Resolutions were introduced December 22, 1847.

³ The Louisiana Purchase: Treaty Between the United States of America and the French Republic, April 30, 1803. Available at: https://avalon.law.yale.edu/19th_century/louis1.asp

⁴ For Jefferson’s constitutional doubts, see his letter to John Breckinridge, August 12, 1803. Available at: https://founders.archives.gov/documents/Jefferson/01-41-02-0139

⁵ Thornton, Russell. *American Indian Holocaust and Survival: A Population History Since 1492*. University of Oklahoma Press, 1987.

⁶ Indian Removal Act, May 28, 1830, 21st Congress, 1st Session, Chapter 148.

⁷ *Worcester v. Georgia*, 31 U.S. (6 Pet.) 515 (1832). See also *Cherokee Nation v. Georgia*, 30 U.S. (5 Pet.) 1 (1831), in which Marshall established the “domestic dependent nations” framework.

⁸ The attribution to Jackson is disputed. See Garrison, Tim Alan. *The Legal Ideology of Removal: The Southern Judiciary and the Sovereignty of Native American Nations*. University of Georgia Press, 2002, pp. 122-124.

⁹ Perdue, Theda and Michael D. Green. *The Cherokee Nation and the Trail of Tears*. Penguin, 2007, pp. 141-160.

¹⁰ Merry, Robert W. *A Country of Vast Designs: James K. Polk, the Mexican War and the Conquest of the American Continent*. Simon & Schuster, 2009, pp. 221-245.

¹¹ Polk, James K. War Message to Congress, May 11, 1846. Available at: https://millercenter.org/the-presidency/presidential-speeches/may-11-1846-war-message-congress

¹² Treaty of Guadalupe Hidalgo, February 2, 1848. Available at: https://avalon.law.yale.edu/19th_century/guam.asp

¹³ For the Wilmot Proviso and its consequences, see: Morrison, Michael A. *Slavery and the American West: The Eclipse of Manifest Destiny and the Coming of the Civil War*. University of North Carolina Press, 1997.

¹⁴ Grant, Ulysses S. *Personal Memoirs of U.S. Grant*. Charles L. Webster & Company, 1885, Volume I, Chapter VIII.

¹⁵ For the Trent Affair, see: Jones, Howard. *Blue & Gray Diplomacy: A History of Union and Confederate Foreign Relations*. University of North Carolina Press, 2010, pp. 82-112.

¹⁶ Grant, Ulysses S. Special Message to the Senate on Santo Domingo, May 31, 1870.

¹⁷ Sumner, Charles. Speech in the Senate opposing Santo Domingo annexation, December 21, 1870. *Congressional Globe*, 41st Congress, 3rd Session.

¹⁸ Treaty with Russia for the Purchase of Alaska, March 30, 1867.

¹⁹ For the Hawaiian revolution and annexation controversy, see: Dougherty, Michael. *To Steal a Kingdom: Probing Hawaiian History*. Island Style Press, 1992.

²⁰ Blount, James H. Report to the Secretary of State on Hawaiian affairs, July 17, 1893.

²¹ Cleveland, Grover. Special Message to Congress on Hawaiian affairs, December 18, 1893. Available at: https://millercenter.org/the-presidency/presidential-speeches/december-18-1893-message-regarding-hawaiian-annexation

²² Strong, Josiah. *Our Country: Its Possible Future and Its Present Crisis*. Baker & Taylor, 1885.

²³ For Social Darwinism and Anglo-Saxonism in American expansion, see: Hofstadter, Richard. *Social Darwinism in American Thought*. Beacon Press, 1955.

²⁴ Mahan, Alfred Thayer. *The Influence of Sea Power Upon History, 1660-1783*. Little, Brown, 1890.

²⁵ Turner, Frederick Jackson. “The Significance of the Frontier in American History,” address to the American Historical Association, July 12, 1893.

Additional Sources on Native American History

Hämäläinen, Pekka. *The Comanche Empire*. Yale University Press, 2008. Essential revisionist history demonstrating Comanche power and agency.

Ostler, Jeffrey. *Surviving Genocide: Native Nations and the United States from the American Revolution to Bleeding Kansas*. Yale University Press, 2019.

Dunbar-Ortiz, Roxanne. *An Indigenous Peoples’ History of the United States*. Beacon Press, 2014.

Calloway, Colin G. *The Indian World of George Washington: The First President, the First Americans, and the Birth of the Nation*. Oxford University Press, 2018.

Saunt, Claudio. *Unworthy Republic: The Dispossession of Native Americans and the Road to Indian Territory*. W.W. Norton, 2020.

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