America has been at war for 233 of its 250 years

By James J. Devine

The United States celebrated its 250th birthday this year with fireworks, flags, military flyovers, and solemn speeches about liberty and peace. The fireworks, at least, were historically appropriate.

America was born shooting and for most of the quarter-millennium that followed, somebody, somewhere, has been on the receiving end of American gunfire. By a broad accounting of wars, interventions, and armed campaigns, U.S. forces have been involved in conflict during roughly nine of every 10 years since 1776.

By one widely circulated accounting that treats wars, frontier campaigns, occupations, punitive expeditions and other sustained combat operations as years of conflict, the United States has been engaged in military hostilities during roughly 233 of its 250 years — more than 93% of its existence.

That number is not an official government statistic, but while the Congressional Research Service has documented hundreds of instances in which U.S. armed forces were used abroad, the 90%-plus figure comes from private year-by-year tallies using an exceptionally broad definition of war.

But quibble over the denominator and the central fact remains hard to escape: For a nation whose political vocabulary is crowded with peace, the United States has spent an astonishing amount of its history fighting.

The American story begins with the Revolutionary War, rolls almost immediately into frontier warfare against Native peoples, sails into naval combat with France and the Barbary states, marches into Canada and Mexico, tears itself apart in civil war, acquires an overseas empire after fighting Spain, occupies countries across the Caribbean and Central America, crosses the Atlantic for two world wars and then settles into a modern era of Korea, Vietnam, Grenada, Panama, the Persian Gulf, the Balkans, Afghanistan, Iraq, Libya, Syria, Somalia and Yemen.

And in 2026, while birthday bunting was being hung from the nation’s porches, American bombs are once again falling abroad.

Five declared wars, an encyclopedia of everything else

The Constitution gives Congress the power to declare war.

Congress has formally exercised it only 11 times, involving five wars: the War of 1812, the Mexican-American War, the Spanish-American War, World War I, and World War II.

The last formal declaration came during World War II.

Every major American war since has been fought without one.

Korea was prosecuted under President Harry Truman as part of an international “police action” authorized by the United Nations Security Council.

Vietnam escalated after Congress adopted the Gulf of Tonkin Resolution, which gave President Lyndon B. Johnson the power to use military force in Southeast Asia without a formal declaration of war.

To enforce United Nations Security Council Resolution 678 and remove Iraqi forces from Kuwait, Congress authorized military force before the 1991 Persian Gulf War.

The attacks of Sept. 11, 2001, produced an Authorization for Use of Military Force so durable that presidents of both parties used it for military operations far removed in time and geography from the organization that attacked America that morning.

Congress passed another authorization before the 2003 invasion of Iraq. The 1991 and 2002 Authorizations for Use of Military Force (AUMFs) against Iraq were not repealed until December 18, 2025.

President Donald Trump, who signed the repeal into law as part of the Fiscal Year 2026 National Defense Authorization Act (NDAA), subsequently ordered maritime strikes in the Caribbean, a military incursion against Venezuela, and bombing in Iran without authorization.

Thus developed one of the peculiar arrangements of modern American democracy: The nation became exceedingly accomplished at going to war without actually declaring one.

Declarations became rare.

Bombs did not.

A continent conquered before an empire was built

Even the familiar list of overseas wars understates the history.

For generations, warfare was conducted inside what would become the continental United States as federal troops, state militias, and settlers fought Native American nations from the Appalachians to the Pacific.

Those campaigns were sometimes called wars, sometimes battles, sometimes removals, and sometimes pacification.

The people being driven from their homes were unlikely to have appreciated the vocabulary lesson.

The 19th century also brought the Mexican-American War, after which Mexico ceded an enormous territory that eventually became California, Nevada and Utah, most of Arizona and New Mexico, and portions of several other states.

Then came the Civil War, the bloodiest conflict in American history.

By the end of that century, the country’s military gaze had moved offshore.

Victory over Spain in 1898 left the United States controlling Puerto Rico, Guam and the Philippines and exercising tremendous influence over Cuba.

American forces subsequently fought a brutal war in the Philippines.

During the decades that followed, Marines became frequent visitors to Latin America and the Caribbean.

Haiti was occupied from 1915 to 1934.

U.S. forces occupied the Dominican Republic, intervened repeatedly in Nicaragua and deployed elsewhere throughout a period remembered as the Banana Wars.

The names change considerably when read from Washington rather than from Managua or Port-au-Prince.

In Washington, they were interventions.

To the people looking up at foreign troops, the distinction could become academic.

America became the arsenal—and police—of the world

World War II transformed the United States into the predominant Western military power.

Unlike Europe and much of Asia, the American homeland emerged largely physically untouched. Its factories were enormous. Its Navy spanned the oceans. Its nuclear monopoly, although brief, announced that warfare had entered a new age.

Then came the Cold War.

The United States fought in Korea.

It fought in Vietnam.

It participated in coups, proxy wars, covert actions and military interventions around the world.

It invaded Grenada in 1983.

It invaded Panama in 1989.

It led a massive coalition against Iraq in 1991.

It conducted military operations in Somalia and the Balkans during the 1990s.

And then came Sept. 11.

The “war on terror” eventually stretched across continents, presidential administrations, and generations of American soldiers.

Afghanistan lasted nearly 20 years.

The Iraq War began in 2003.

American forces conducted operations in Syria, Somalia, Yemen, and elsewhere.

The Brown University Costs of War project has documented the extraordinary financial and human consequences of America’s post-9/11 military campaigns. Even after U.S. forces left Afghanistan in 2021, the bills — including veterans’ care and interest on money borrowed for war — continued to accumulate.

A war, it turns out, can end for the Pentagon long before it ends for the taxpayer, the amputee or the widow.

Afghanistan ended. American combat did not.

The withdrawal from Afghanistan in August 2021 ended America’s longest major war.

It did not inaugurate an age of peace.

American forces continued counterterrorism missions in Somalia, Syria and elsewhere.

Beginning after the Oct. 7, 2023, Hamas attack on Israel, the United States dramatically expanded military activity across the Middle East. American warships fought Houthi forces around the Red Sea and the Gulf of Aden, and U.S. forces carried out more than 1,000 airstrikes in the region through September 2025, according to Brown University’s Costs of War project.

Then 2026 arrived.

On Jan. 3, U.S. forces carried out a large-scale military operation in Venezuela that captured President Nicolás Maduro after strikes around Caracas and other locations. It was America’s most consequential direct military intervention in Latin America since the 1989 invasion of Panama.

Brown University researchers estimate U.S. military operations in Venezuela, the Caribbean and eastern Pacific cost at least $4.7 billion between Aug. 1, 2025, and March 31, 2026.

Then came Iran.

On Feb. 28, U.S. and Israeli forces launched massive strikes against Iran. The Pentagon named the American campaign Operation Epic Fury.

Within its first 29 days, U.S. Central Command said American forces had conducted more than 11,000 combat flights, struck more than 11,000 targets, and damaged or destroyed more than 150 Iranian vessels.

The fighting killed thousands, disrupted energy markets and pushed the United States into another sprawling Middle Eastern conflict. Hostilities and confrontations continued into August amid faltering diplomatic efforts.

So much for the peace dividend.

The great constitutional disappearing act

The most remarkable feature of modern American warfare may not be how often the country fights.

It may be how ordinary fighting has become.

The Constitution’s framers put the power to declare war in Congress because taking a republic into war was supposed to be among the gravest decisions its government could make.

Yet Congress has not formally declared one since 1942, when it declared war against Axis-aligned governments during World War II.

Presidents nevertheless have dispatched bombers, missiles, aircraft carriers, drones, special operations forces and infantry into conflicts large and small.

Sometimes Congress authorized force.

Sometimes presidents relied on old authorizations.

Sometimes administrations asserted inherent constitutional authority.

Sometimes lawmakers protested.

Then they appropriated the money.

The constitutional power of Congress to declare war remains beautifully preserved, rather like the good china in a cabinet: admired on special occasions and seldom brought out for actual use.

War by euphemism

America has also developed an impressive thesaurus for avoiding the unpleasant little word.

There have been police actions.

Peacekeeping missions.

Limited military operations.

Counterterrorism missions.

Security operations.

Humanitarian interventions.

No-fly zones.

Advisory missions.

Surgical strikes.

Over-the-horizon capabilities.

And, naturally, operations bearing names that sound as though selected by a committee instructed to combine virtue with explosives.

The vocabulary may change.

A Hellfire missile does not.

That is why any claim that America has been “at war” for 233 of 250 years requires a warning label. Counting a four-day intervention in Grenada the same way as four years of World War II obviously flattens enormous differences in scale, casualties, purpose and legality.

But the reverse trick is equally misleading.

Counting only formally declared wars would make Korea, Vietnam, Afghanistan and Iraq somehow less than wars, an interpretation unlikely to impress the millions who served in them.

The honest historical picture lies between those extremes.

America has not spent literally every moment of 233 years conducting major warfare.

It has, however, resorted to organized military force with extraordinary frequency throughout nearly every period of its national existence.

The republic and the arsenal

There are defensible explanations for many American wars.

The Revolution established independence.

The Civil War preserved the Union and destroyed legal slavery.

World War II defeated fascist regimes that had launched catastrophic wars of conquest.

Other interventions have been justified as collective defense, counterterrorism, protection of shipping, prevention of atrocities, or defense of allies.

Wars cannot responsibly be dumped into one moral bucket merely because soldiers carried the same flag.

But neither should America’s extraordinary reliance on military force disappear beneath 250th-anniversary mythology.

There is a difference between saying every American war was wrong and asking why war has appeared so frequently in American history.

That question becomes particularly uncomfortable when set beside the numbers.

Congress has formally declared war in only five conflicts.

The Congressional Research Service nevertheless has cataloged hundreds of uses of American armed forces abroad since 1798, ranging from anti-piracy expeditions and protection of citizens to invasions and enormous sustained wars.

America’s political leaders have spent generations praising peace while maintaining the most powerful military machinery on Earth.

The nation has produced statesmen who warned against entanglements, presidents who campaigned against wars and generations of voters who said they wanted the troops home.

Yet the troops keep finding someplace else to go.

A birthday worth celebrating — and examining

The United States at 250 remains an extraordinary political experiment.

It has survived civil war, economic catastrophe, political violence, presidential assassinations, segregation, terrorism, and repeated assaults on its democratic ideals.

Its accomplishments are real.

So are its battlefields.

A mature nation ought to be able to remember both.

There will be plenty of patriotic speeches in 2026 about the shot heard round the world.

There may be fewer speeches about all the shots that followed.

The precise claim that America has fought during 233 of its 250 years depends upon definitions broad enough to include conflicts that historians would classify very differently. It is better understood as a provocative measure of recurring American military activity than as a literal government-certified count of years at war.

But after 250 years, perhaps the most unsettling fact is that the arithmetic barely needs exaggeration to make its point.

The United States was born in war.

It expanded amid war.

It became a world power through war.

It built a global military system after war.

As Americans gather to celebrate two and a half centuries of independence, United States military forces are fighting once again.

Two hundred fifty candles fit on the national birthday cake. Finding enough room between them for all the battle ribbons may be the harder job.