Foreign interventions by the United States

Based on Wikipedia: Foreign interventions by the United States

Four hundred military interventions. That's the count between 1776 and 2023—and more than half of them happened after 1950. The United States, a nation founded in revolution against empire, became the most interventionist power in modern history. How did that happen?

Two Souls of American Foreign Policy

From the beginning, Americans have been of two minds about the world beyond their borders.

On one side: interventionism—the belief that America should actively shape global affairs through military force, economic pressure, and political maneuvering. On the other: isolationism—the conviction that the nation is better served by minding its own business and letting other countries sort out their own problems.

These aren't just policy positions. They're almost religious orientations, deeply embedded in the American psyche. George Washington warned against "entangling alliances" in his farewell address. Yet within a decade of his death, the young nation was launching naval expeditions against North African pirates. The tension has never been resolved—it just gets rebalanced with each generation.

The Nineteenth Century: Merchants, Marines, and Manifest Destiny

America's first foreign wars weren't fought for ideology. They were fought for commerce.

The Barbary Wars of the early 1800s established a pattern that would repeat for two centuries. Pirates from the North African coast—modern-day Libya, Tunisia, Algeria, and Morocco—had been seizing American merchant ships and enslaving their crews. European nations paid tribute to make the raids stop. The young United States decided to fight instead.

It was a decisive choice. Rather than buy peace, America built a navy and projected force across an ocean. The phrase "shores of Tripoli" in the Marine Corps Hymn commemorates these campaigns. They set a precedent: when American economic interests face threats abroad, military options are on the table.

Back home, the century's great project was continental expansion. President James K. Polk embraced Manifest Destiny—the belief that American settlement across North America was not just desirable but divinely ordained. The 1803 Louisiana Purchase doubled the nation's size overnight. The 1846 Mexican-American War added California, Texas, and the entire Southwest. By mid-century, American territory stretched from Atlantic to Pacific.

This expansion wasn't intervention in the sense of meddling in foreign affairs. It was conquest. But it created the territorial foundation—and the military habits—that would eventually support global power projection.

Opening Closed Doors

Commodore Matthew Perry's 1854 expedition to Japan illustrates how economic interests drove early American interventionism. Japan had been deliberately isolated from the Western world for over two centuries. The Tokugawa shogunate had expelled foreigners, banned Christianity, and executed Japanese citizens who attempted to leave or return from abroad.

Perry arrived with four warships—"black ships," the Japanese called them—and a letter from President Millard Fillmore requesting trade relations. The request was backed by obvious naval firepower. Within a year, Japan signed the Convention of Kanagawa, opening two ports to American ships and ending its long isolation.

The consequences were enormous. Japan's forced opening triggered political upheaval that culminated in the Meiji Restoration, which transformed the country from a feudal society into an industrial power. Within fifty years, Japan would defeat Russia in war and begin building its own empire. The Perry expedition demonstrates how American interventions can set off chain reactions that reshape entire regions for generations.

Meanwhile, in China, the United States launched the Yangtze Patrol in 1854—a naval operation that would continue for nearly a century. American gunboats cruised China's rivers and coastal waters, protecting merchant ships and American citizens in the treaty ports that Western powers had extracted from a weakening Qing dynasty. The patrol ended only in 1949, when Mao Zedong's forces won the Chinese Civil War and expelled all foreign military presence.

Korea, Samoa, and the Patterns of Gunboat Diplomacy

The 1871 Korean expedition shows how quickly commerce could turn to conflict. When an American merchant ship, the General Sherman, was attacked while trying to force open trade with the isolationist Korean kingdom, the United States sent an expeditionary force. After being ambushed, the 650-man force launched a punitive campaign, capturing Korean forts and killing over 200 Korean soldiers.

Korea remained closed. The expedition failed in its stated objective. But the willingness to project military force across the Pacific—to send hundreds of men to fight on the Korean peninsula—established capabilities and habits of mind that would matter greatly in later centuries.

The 1887 Samoan crisis introduced another recurring theme: competition with European powers over Pacific real estate. The United States and Germany both wanted control of the Samoan Islands, strategically located in the South Pacific. Naval forces from both nations engaged in a months-long standoff during a Samoan civil war. The standoff ended only when a cyclone wrecked all six ships involved—a divine intervention, some said, preventing a war between two rising powers.

The islands were eventually partitioned. American Samoa remains a United States territory today. German Samoa—later Western Samoa, now simply Samoa—became an independent nation.

1898: The Year Everything Changed

The Spanish-American War lasted barely four months. Its consequences lasted a century.

The war began over Cuba. Spain's brutal suppression of a Cuban independence movement outraged American public opinion, stoked by sensationalist newspaper coverage. When the battleship USS Maine exploded in Havana harbor—probably due to an accidental coal fire, though Americans blamed a Spanish mine—war fever became irresistible.

The actual fighting was remarkably one-sided. American naval forces destroyed Spanish fleets in both Cuba and the Philippines. Army troops, including Theodore Roosevelt's famous Rough Riders, invaded Cuba. Within months, Spain sued for peace.

The peace treaty transformed the United States into an imperial power. Spain ceded Puerto Rico, Guam, and the Philippines. Cuba became nominally independent but effectively a protectorate—the Platt Amendment of 1901 gave the United States the right to intervene in Cuban affairs and established the naval base at Guantánamo Bay, which remains American territory today.

The Philippines presented a moral dilemma that Americans have never fully resolved. Filipino revolutionaries, who had been fighting Spanish rule, expected independence. Instead, the United States annexed the islands. When Filipinos resisted, the result was the Philippine-American War—a brutal counterinsurgency that lasted until 1902, with related conflicts continuing until 1913.

The United States deployed 100,000 troops to the Philippines, most of them National Guard soldiers. The poorly armed Filipino insurgents were crushed militarily but never fully pacified. Estimates of Filipino civilian deaths range from 200,000 to over a million, many from war-related famine and disease.

The war troubled American consciences. Anti-imperialist leagues formed. Mark Twain wrote bitter satires. But the empire expanded anyway. The United States had become, whether it acknowledged it or not, a colonial power with possessions spanning the Pacific.

The Roosevelt Corollary and Dollar Diplomacy

With the Spanish empire broken, the United States faced a new question: what to do about the rest of Latin America?

The Monroe Doctrine, proclaimed in 1823, had declared the Western Hemisphere off-limits to European colonization. But by the early 1900s, European powers were finding other ways to exert influence—particularly by extending loans to unstable Latin American governments, then using debt collection as a pretext for military intervention.

Theodore Roosevelt's solution was characteristically bold. In 1904, he announced what became known as the Roosevelt Corollary to the Monroe Doctrine. The United States would not merely prevent European intervention in Latin America—it would intervene itself whenever chronic instability in the region might invite European meddling.

This was intervention as preventive medicine. If a Latin American country couldn't manage its affairs—couldn't pay its debts, couldn't maintain order—the United States would step in before Europeans could. The logic was circular but effective: American dominance in the hemisphere was justified as necessary to prevent European dominance.

The results were extraordinary. Between 1898 and 1935, the United States launched military interventions throughout Central America and the Caribbean. Marines occupied Cuba, Haiti, the Dominican Republic, and Nicaragua for years at a time. Customs houses were seized, governments propped up or toppled, elections supervised.

President William Howard Taft refined this approach into what became known as "Dollar Diplomacy"—the use of economic investment and financial pressure as tools of foreign policy. American banks and corporations would invest in Latin American countries. The United States government would protect those investments. Local governments, dependent on American capital, would align with American interests.

The Marines became the instrument of this policy. The Small Wars Manual, published by the Marine Corps, codified their role as expeditionary forces—not fighting major wars but policing countries in America's sphere of influence, safeguarding customs revenues, suppressing insurgencies, maintaining order.

Case Study: The Dominican Republic

The Dominican Republic illustrates how deeply the United States became entangled in its neighbors' affairs. In the fifty years before American intervention, the country had experienced twenty-eight revolutions. Political instability was chronic, debt was crushing, and European creditors were circling.

In 1916, United States Marines landed and took control. They would stay for eight years.

The occupation was comprehensive. Marines ruled the country completely except for lawless sections of Santo Domingo where local warlords maintained power. They built roads, established schools, created a constabulary force. They also suppressed dissent, sometimes brutally.

When the Marines finally withdrew in 1924, they left behind Rafael Trujillo—a Dominican military officer they had trained. Trujillo would seize power in 1930 and rule as one of Latin America's most brutal dictators until his assassination in 1961. American intervention had created a monster.

The World Wars: From Reluctant Entry to Global Power

The First World War nearly undid American interventionism.

President Woodrow Wilson campaigned for reelection in 1916 on the slogan "He kept us out of war." When German submarine attacks on American shipping finally forced his hand in 1917, Wilson justified intervention in idealistic terms—this would be "the war to end all wars," a crusade to "make the world safe for democracy."

American troops tipped the balance on the Western Front. But the cost was staggering: 116,708 Americans killed, 204,002 wounded. And the peace that followed seemed to vindicate every isolationist argument. The Treaty of Versailles created new problems even as it solved old ones. The League of Nations, Wilson's dream of collective security, was rejected by the United States Senate.

The 1930s saw a decisive turn away from global engagement. Congress passed a series of Neutrality Acts designed to prevent the entanglements that had drawn America into the Great War. Arms sales to belligerents were banned. American citizens were forbidden from traveling on belligerent ships. The legislation was a systematic attempt to insulate the United States from foreign conflicts.

It couldn't last.

As Nazi Germany conquered Europe and Imperial Japan expanded across Asia, the contradictions of American neutrality became untenable. President Franklin Roosevelt found ways to help Britain survive—the "destroyers for bases" deal of 1940 transferred fifty American warships to the Royal Navy in exchange for military bases throughout the British Empire. The Lend-Lease program that followed was neutrality in name only; the United States was arming the Allies on a massive scale.

Japan's attack on Pearl Harbor on December 7, 1941 ended the debate. Germany declared war on the United States four days later. For the next four years, American forces fought across three continents and two oceans.

The scale of the effort was unprecedented. Over 400,000 Americans died. The Two-Ocean Navy Act of 1940 had increased the United States Navy by seventy percent; by war's end, it was the most powerful naval force in human history. American industry produced ships, planes, tanks, and ammunition in quantities that overwhelmed Axis powers.

When the fighting stopped, American troops didn't come home—not all of them. They remained in Germany and Japan, occupying the defeated powers and rebuilding them as democracies and market economies. Seventy-five years later, American forces are still there.

The Cold War: Containment and Its Consequences

The alliance that won World War II fractured almost immediately. The Soviet Union, which had suffered catastrophic losses fighting Nazi Germany, was determined to create a buffer zone of friendly states in Eastern Europe. The United States, which emerged from the war as the world's dominant economic and military power, was equally determined to prevent Soviet expansion.

The result was the Cold War—forty-five years of ideological, political, and occasionally military confrontation that shaped American interventionism in ways still felt today.

The policy that defined American strategy was containment: preventing the spread of communism rather than trying to roll it back. First articulated by diplomat George Kennan in 1946, containment became official doctrine under President Harry Truman. The Truman Doctrine committed the United States to supporting "free peoples who are resisting attempted subjugation by armed minorities or by outside pressures"—a mandate for intervention anywhere communism threatened.

Each subsequent president added his own doctrine. Eisenhower pledged to use American forces to protect Middle Eastern countries against communist aggression. Kennedy committed to "pay any price, bear any burden" in defense of liberty. Carter declared the Persian Gulf a vital American interest. Reagan supported anti-communist insurgencies worldwide.

The interventions that resulted ranged from covert operations to major wars. The Central Intelligence Agency, established in 1947, became a primary instrument of American power projection—organizing coups, training guerrillas, conducting propaganda campaigns. In 1953, the CIA helped overthrow Iran's elected government. In 1954, it toppled Guatemala's. Throughout the Cold War, the agency operated in dozens of countries, often with little congressional oversight.

Korea and Vietnam were the major wars. Korea, from 1950 to 1953, established the template: an American-led United Nations force defending a pro-Western government against communist invasion. The war ended in stalemate, with the peninsula divided along roughly the same line where fighting began. Over 36,000 Americans died.

Vietnam was far more traumatic. American involvement escalated gradually through the 1950s and early 1960s, then exploded after 1965. At the war's peak, over 500,000 American troops were deployed. By the time Saigon fell in 1975, more than 58,000 Americans had died, along with millions of Vietnamese, Cambodians, and Laotians.

Vietnam didn't end American interventionism. But it changed its character. Future presidents would seek to avoid "another Vietnam"—prolonged ground wars with ambiguous objectives and mounting casualties. The preference shifted toward air power, special operations, and proxy forces.

After the Cold War: The Sole Superpower

The Soviet Union collapsed in 1991. The Cold War ended not with a bang but with economic exhaustion and political dissolution. The United States emerged as what commentators called the "sole superpower"—dominant in military, economic, and cultural terms to a degree unprecedented since the Roman Empire.

What would America do with this power?

The answer, it turned out, was: intervene. A lot.

The 1990s saw American forces deployed to Somalia, Haiti, Bosnia, and Kosovo. Some interventions were humanitarian—attempting to stop famine or genocide. Others were more traditional exercises of geopolitical influence. None achieved lasting success; Somalia in particular became a cautionary tale after the "Black Hawk Down" incident of 1993 killed eighteen American soldiers and prompted withdrawal.

But these were minor operations compared to what came after September 11, 2001.

The War on Terror

The attacks of September 11 killed nearly 3,000 people and transformed American foreign policy. President George W. Bush declared a "global war on terror" with no geographic limits and no defined endpoint.

Afghanistan came first. The Taliban government had provided sanctuary to al-Qaeda, the terrorist organization responsible for the attacks. American forces, supported by local Afghan allies, toppled the Taliban within months. The initial campaign seemed an astonishing success.

Iraq followed in 2003. The Bush administration claimed that Saddam Hussein possessed weapons of mass destruction and had links to terrorism. Both claims proved false. But American and British forces invaded anyway, toppling Hussein's government in weeks.

What came next was chaos. Neither Afghanistan nor Iraq proved amenable to the nation-building that American planners envisioned. Insurgencies erupted. Sectarian violence exploded. American troops found themselves fighting guerrilla wars remarkably similar to Vietnam—without clear objectives, without effective local allies, without any obvious path to victory.

The costs were enormous. Over 7,000 American service members died in the two conflicts. Trillions of dollars were spent. Hundreds of thousands of Afghans and Iraqis perished. The democratic governments that American intervention was supposed to establish proved weak and corrupt.

Afghanistan ended in debacle. In August 2021, American forces withdrew and the Taliban retook control within days. Twenty years of intervention had produced nothing lasting.

The Pivot to Asia and the New Great Power Competition

Even as the wars in Afghanistan and Iraq ground on, American strategists were looking elsewhere. China's rise was transforming global politics. The Obama administration announced a "Pivot to Asia" in 2012—a strategic reorientation away from Middle Eastern counterinsurgency toward managing China's growing power.

The pivot involved strengthening alliances with Japan, South Korea, Australia, and other Asian nations. It meant increasing naval presence in the western Pacific, particularly around the disputed waters of the South China Sea where China was building artificial islands and asserting expansive territorial claims. It represented a return to great power competition after two decades focused on terrorism and insurgency.

Subsequent administrations have continued this trajectory. The Trump and Biden administrations both embraced the "Free and Open Indo-Pacific" strategy, emphasizing freedom of navigation, multilateral cooperation, and resistance to Chinese expansionism. American forces have reinforced what strategists call the "first island chain"—the arc of islands from Japan through Taiwan and the Philippines that contains Chinese naval power.

Whether this competition will remain cold or eventually turn hot is the defining geopolitical question of our era. Taiwan, which China claims as its territory and the United States is committed to defending, represents the most dangerous flashpoint. An American military intervention to defend Taiwan against Chinese invasion would be the largest conflict the United States has fought since World War II.

The Instruments of Power

American interventionism rests on capabilities that no other nation can match.

The United States Navy operates the world's only global blue-water fleet—a navy capable of projecting power anywhere on Earth. Eleven nuclear-powered aircraft carriers serve as mobile airbases. Hundreds of other vessels—cruisers, destroyers, submarines, amphibious ships—support them. No other nation has more than two carriers.

The United States Air Force possesses strategic airlift and global strike capabilities unmatched anywhere. Heavy transport aircraft can move troops and equipment to any continent. Bombers can strike targets worldwide, either from American bases or from forward deployments. Aerial refueling extends the range of any aircraft indefinitely.

Special operations forces—Navy SEALs, Army Green Berets, Air Force pararescuemen, and others—conduct clandestine missions in countries where conventional forces cannot openly operate. These units train foreign militaries, advise allied governments, hunt terrorists, and occasionally conduct direct-action raids like the one that killed Osama bin Laden.

Behind all of this stands an intelligence community of unprecedented size and sophistication. The Central Intelligence Agency, the National Security Agency, and a constellation of other agencies monitor global communications, recruit foreign agents, and conduct covert operations that rarely become public.

The network of American military bases spans the globe. Status of forces agreements with dozens of countries permit American troops to be stationed on foreign soil. No other nation maintains a comparable overseas military presence.

The Paradox of American Power

Four hundred interventions. Trillions of dollars. Millions of lives.

What has it achieved?

The honest answer is: mixed results at best. Some interventions succeeded—the occupations of Germany and Japan after World War II created stable democracies and enduring alliances. Others failed catastrophically—Vietnam, Iraq, and Afghanistan consumed decades and vast resources without achieving their objectives.

The pattern that emerges from two centuries of American interventionism is sobering. Military force can topple governments quickly. It cannot build stable societies. It can win battles. It cannot win hearts and minds. It can project power. It cannot always achieve policy goals.

Yet American interventionism continues. The capabilities exist. The political culture supports their use. When crises erupt abroad—when terrorists strike, when dictators commit atrocities, when allies face threats—the question is always asked: what will America do?

The answer, more often than not, is: something. Four hundred interventions and counting.