The United States has the largest economy in the world. It has held that title for more than a century, and the gap between America and the rest of the world remains enormous. The US economy produces more than a quarter of everything the world makes, and its currency, the dollar, is the money that the rest of the world uses to trade, to save, and to borrow.
It was not always this way. In 1800, the United States was a small, agricultural country on the edge of the Atlantic, with a population of about five million people and an economy that was a fraction of the size of Britain’s or China’s. By 1900, it had become the largest economy in the world, and it has stayed there ever since.
How did it happen? The answer is not a single event or a single policy. It is a story of land, people, resources, and institutions, and of a country that was built to grow.
The Land and the Resources
The first advantage America had was land, and lots of it. The United States covers nearly 3.8 million square miles, making it one of the largest countries on Earth. That land contains some of the most productive farmland in the world, vast forests, abundant fresh water, and enormous deposits of coal, oil, natural gas, iron, and other resources.
The farmland alone was transformative. The Great Plains, the vast grasslands of the American Midwest, became the breadbasket of the world, producing wheat, corn, and soybeans in quantities that no other country could match. The Mississippi River system, the largest navigable river network in the world, provided a cheap way to move those crops to market, and to move manufactured goods back inland.
The country’s natural resources also fueled its industrial growth. Coal from Appalachia powered the factories of the Northeast. Iron ore from Minnesota fed the steel mills of Pittsburgh and Gary. Oil from Texas and later from the Gulf of Mexico and the shale fields of North Dakota made the United States the world’s largest oil producer. The country was, in a very real sense, built on what was under its feet.
The People and the Immigration
Land and resources are not enough on their own. An economy needs people, and the United States had a remarkable ability to attract them. From the early 1800s onward, millions of immigrants came to America from Europe, Asia, Latin America, and Africa, drawn by the promise of land, work, and opportunity. The population grew from about 5 million in 1800 to more than 330 million today, and immigration was a major driver of that growth.
The immigrants brought more than labor. They brought skills, ideas, and ambition, and they built businesses, founded industries, and created new technologies. The American economy has always been an immigrant economy, and its growth has always depended on the willingness of people to come to the United States and build something new.
The country’s population was also young and growing for most of its history, which meant a large and expanding workforce. A growing population creates demand for housing, food, clothing, and services, and it provides the workers to meet that demand. This virtuous cycle of growth was one of the most powerful forces in American economic history.
The Railroads and the Infrastructure
If land and people were the raw materials of American growth, infrastructure was the engine. The most important infrastructure project in American history was the railroad, and it transformed the economy in ways that are hard to overstate.
Before the railroad, moving goods across the country was slow, expensive, and unreliable. The transcontinental railroad, completed in 1869, connected the East Coast to the West Coast for the first time, and the railroad network that followed linked every part of the country into a single national market. A farmer in Iowa could sell wheat to a buyer in New York. A manufacturer in Ohio could ship goods to California. The entire country became one economy.
The railroads also created new industries. Steel production boomed to supply the rails. Coal mining expanded to fuel the locomotives. Towns grew up along the tracks, and cities like Chicago, St. Louis, and Omaha became transportation hubs. The railroad was the internet of its day, a network that connected the country and made it possible for the economy to grow at a scale that had never been seen before.
The infrastructure story did not end with the railroads. In the 20th century, the United States built the interstate highway system, the largest public works project in American history, which connected the country by road and made it possible for goods and people to move freely from coast to coast. The country also built a vast system of airports, ports, and telecommunications networks, all of which reinforced its position as the world’s largest economy.
Innovation and the Institutions
America’s economic rise was also a story of innovation. The country was an early leader in the technologies that defined the modern world, from the telegraph and the telephone to the automobile, the airplane, and the computer. American inventors and entrepreneurs, from Thomas Edison to Henry Ford to Steve Jobs, created industries that changed the world, and the American system of patents, universities, and venture capital helped turn ideas into businesses.
The country’s institutions also mattered. The United States had a stable system of property rights, a reliable legal system, and a government that, for most of its history, supported economic growth through investments in infrastructure, education, and research. The Federal Reserve, established in 1913, provided a stable monetary system. The country’s capital markets, centered on Wall Street, provided the financing that businesses needed to grow.
None of this was inevitable. Other countries had land, resources, and people, but they did not have the same combination of institutions, infrastructure, and openness to immigration. The American economy grew because the country was built to grow, and because it kept investing in the things that made growth possible.
The American Economy Today
Today, the United States economy is the largest in the world by a wide margin, with a gross domestic product that the International Monetary Fund estimates at roughly 30 trillion dollars. The country is the world’s largest consumer market, the world’s largest importer, and one of its largest exporters. American companies dominate the global technology industry, American universities are among the best in the world, and the dollar remains the world’s reserve currency, the money that central banks hold and that international trade is conducted in.
The economy has also changed dramatically since the days of the railroads and the steel mills. Services now account for the majority of economic activity, and technology, healthcare, and finance are among the largest sectors. Manufacturing remains important, but it is a smaller share of the economy than it once was. The country has also become more deeply integrated into the global economy, with supply chains that stretch around the world and trade relationships that link it to every major economy.
Challenges remain. The national debt is large and growing. Income inequality has widened. Manufacturing jobs have declined in many parts of the country. And other countries, most notably China, have grown rapidly and narrowed the gap. But the United States remains the world’s largest economy, and its advantages, a large and dynamic population, abundant resources, world-class universities, deep capital markets, and a culture of innovation, are not going away.
Frequently Asked Questions
When did the US become the world’s largest economy?
The United States surpassed Britain to become the world’s largest economy around 1900, and it has held the title ever since. The exact year depends on how the economy is measured, but the turn of the 20th century is the commonly cited turning point.
How big is the US economy today?
The US economy has a gross domestic product of roughly 30 trillion dollars, according to estimates from the International Monetary Fund. That is more than a quarter of the entire world’s economic output.
Why is the dollar the world’s reserve currency?
The dollar became the world’s reserve currency after World War II, when the United States was the dominant economic power and the dollar was tied to gold. Even after the gold standard ended, the dollar remained the currency of international trade because of the size and stability of the American economy.
What role did immigration play in America’s economic growth?
Immigration was central to American economic growth. Millions of immigrants provided labor, skills, and entrepreneurship, and the population grew from about 5 million in 1800 to more than 330 million today, largely because of immigration and its effects.
What was the most important infrastructure project in US history?
The railroad network, and especially the transcontinental railroad completed in 1869, is widely considered the most important. It created a single national market and made it possible for the economy to grow at a scale that had never been seen before.
Is China about to overtake the US economy?
China has the world’s second-largest economy and has grown rapidly, but the United States remains well ahead in nominal terms. Whether and when China might overtake the US depends on future growth rates, exchange rates, and how the economy is measured.