The next 250: America’s wars

America was born in war. Armed conflict was a nearly constant feature of its first century of existence. Wars became more sporadic but more violent during its second century. War has persisted to the end of its first quarter-millennium. Will belligerence remain a central feature of the American experience?

It is not inconceivable that America could have gained independence without war. Canada did so, and from the same British empire. Except that it wasn't the same British empire, the original one having been disrupted by the violent departure of the American colonies that became the United States. In the 18th century, the British government was not inclined to release any of its colonies. And the Americans were not inclined to remain within the empire until Britain changed its mind. British stubbornness and American impatience produced the American Revolution, which in turn produced American independence.

America's second war, the undeclared naval conflict with France in the late 1790s, resulted largely from America's insistence on the right to trade with countries France was at war with, and France’s refusal to recognize that right. Trade rights would be a casus belli for the United States into the 20th century.

Trade rights triggered a second war with Britain, starting in 1812. The kidnapping, or impressment, of sailors from American ships was another cause. America’s expansionist objectives figured as well. Americans were full of themselves after purchasing Louisiana from France, and they were still miffed at the refusal of Canada to join the American Revolution. Their war hawks boasted that Canada could be conquered with ease. It couldn't, and wasn't, and the War of 1812 ended in a draw.

Conflict with Indian tribes had been a regular feature of America's colonial existence. It continued into America 's independence. Much of the fighting in the Revolutionary War was against Indian tribes allied with Britain. Their defeat led to Britain's concession of the Ohio valley to the United States in the treaty that ended the war. The War of 1812 broke the back of Tecumseh's Indian alliance, which sided with the British, and led to the rapid settlement of the old southwest. The Blackhawk war of the 1830s did the same for much of the old northwest. The Seminole wars, the Sioux wars, the Modoc war, the Cayuse war, the Apache wars and others unnamed were similarly successful in removing Indians to make way for white farmers and ranchers.

America's war with Mexico, commonly dated 1846 to 1848, really began in the 1830s when American emigrants to Mexican Texas revolted against Mexican rule. The debate over slavery delayed annexation of independent Texas by the United States until 1845. In the process it delayed the war between the United States and Mexico. When that war came it confirmed the transfer of Texas from Mexican control to American, and threw New Mexico and California into the bargain. 

To this point, the addition of territory had been a principal objective of American wars. The Civil War was fought by the Union to prevent the subtraction of territory, namely the territory of the secessionist states. The Civil War accelerated the industrial revolution in America. It also marked the last American war over territory.

The coincidence wasn't accidental. An agrarian country with a growing population—such as the United States in its first century— requires regular additions of territory to support the growing population. An industrial society does not. What an industrial society requires is consumers for what it produces. In the early stages of industrialization, domestic consumers can suffice. But before long, industrial societies seek foreign markets. 

America’s war with Spain in 1898 was about foreign markets, among other things. It started over Cuba but expanded at once to the Philippines, at the doorstep of China's immense potential market. America's military incursions into Mexico, Central America and the Caribbean in the first three decades of the 20th century extended the reach of American capitalism by securing markets and sources of supply and ejecting or preempting European competitors.

America entered World War I after repeated violations of American neutral rights. Woodrow Wilson added the defense of democracy to the American agenda. The idea caught on rhetorically. In nearly every subsequent American war, presidents proclaimed America's intention to defend or expand democracy.

In practice, economic freedom often received priority over political freedom. The economic freedom most sought by presidents was freedom for American merchants and investors in foreign markets.

Franklin Roosevelt specified four freedoms as America joined World War II. Freedom of speech and of worship, freedom from want and from fear rang proudly from the lips of American leaders during that war and the Cold War and after.

These leaders weren't insincere. But they were realistic, and they often put American material interests first. During World War II, America allied with imperialist Britain and communist Russia. Similar pragmatism prompted the United States to go to war on behalf of South Korea and South Vietnam during the Cold War. The governments of those countries weren’t democratic but they were anticommunist.

Which underlined a new theme in the motivation of American wars. The outcome of World War II made America the top dog—the hegemon—in global affairs. Top dogs fight to preserve their primacy. During the Cold War, American leaders couched their goals in terms of containing communism. What they meant was the preservation of American hegemony. Thus the Korean war and the Vietnam war. The Gulf war of 1991 had the goal of containing Saddam Hussein. The Iraq war that started in 2003 finished the job by toppling Saddam. The Afghanistan war of 2001 to 2021 commenced as retaliation for the al-Qaeda attack of September 11, 2001, but continued on its own momentum.

Will America’s next quarter-millennium be as war-filled as its first?

Quite probably at the start. America remains the leading global power, meaning it has much to defend. It faces challenges from China, Russia and Iran. It is already fighting proxy wars against Russia and Iran. A war against China over Taiwan appears increasingly likely. Since World War II, Americans have thought of themselves as the guardians of world order—the pro-American order that emerged in 1945. Such Americans as have expressed skepticism have been shouted down as appeasers and isolationists.

Whether this situation will persist for many decades more is open to doubt. Hegemons don’t hold their positions forever. Commitments multiply and power gets spread thinly. If things should go badly for Ukraine and Israel, and if China should take the opportunity to jump Taiwain, Americans would face the possibility of fighting or assisting on three fronts simultaneously. Something would probably have to give.

No less a challenge to America’s global primacy is the rebalancing of the world economy that has occurred since 1945. At that time America’s industrial GDP equaled the rest of the world’s combined. America could and did dictate the rules of the world order. Eight decades later other countries have closed the gap considerably. America’s economic throw-weight today is half what it was, comparatively speaking. Sooner or later, countries get the foreign policies they can afford. Today America can’t afford what it could at the end of World War II.

Moreover, domestic demands on American resources have grown. Social Security was in its infancy in 1945. Medicare didn’t exist. Those two programs and their spinoffs now dwarf the Pentagon in terms of budget share. Before this century Americans didn’t have to choose between guns and butter. Now they do and henceforth they will. 

No single country is about to replace America as global hegemon. But the world as a whole has become less manageable for the United States. How American leaders negotiate their country’s climb down the mountain will determine how often America goes to war. Britain made its transition after World War II with reasonable grace and only modest violence. But Britain had the comfort of handing its responsibilities to a country it trusted, namely America. No such friendly heir to American hegemony is in sight.

Whether America continues to fight wars is wrapped in the question of whether wars in general will be as frequent in the future as they have been in the past. Thankfully, world war has been avoided since 1945, possibly because of the existence of nuclear weapons. But regional wars and civil wars persist. And hostilities short of war—insurgencies, terrorism, cyberwarfare—show no sign of diminishing.

America’s exposure to attack will depend on how ambitious American foreign policy remains. If America continues to support Israel and to try to contain Iran, it will continue to tempt the enemies of Israel and the agents of Iran to attack Americans and American allies. If America continues to back Ukraine and impose sanctions on Russia, Russia will have an incentive to strike at America. American leaders and the American people may decide that the benefits of these policies outweigh the costs, but they may decide differently. America has withdrawn from other troubled spots—Vietnam, Iraq, Afghanistan—and reduced its exposure.

Certain of the causes of America’s wars have vanished or diminished. America will not fight wars for territory, as it once did. Territory per se means little in a post-industrial age. America won’t fight wars to open markets. Trade operates differently now.

Yet America might still fight to preserve its leadership role in the world. For how long? Until America is no longer the leader, and Americans come to terms with that fact.