The United States as a World Power

Instructor: Nate Sullivan

Nate Sullivan holds a M.A. in History and a M.Ed. He is an adjunct history professor, middle school history teacher, and freelance writer.

In this lesson we will learn about the emergence of the United States as a world power. We will examine the context in which the United States emerged as a world power, and we will highlight key terms associated with this development.

Humble Beginnings

April 19th, 1775, near Lexington and Concord, Massachusetts: a shot rings out. It becomes known as the 'Shot Heard 'Round the World' because it ignites a world war. In American history, this world war is known as the American Revolution, or more accurately the Revolutionary War. This small act sets in motion events that will lead to the emergence of the United States as a world power.

When the thirteen British colonies broke away from Great Britain and became the United States of America, they had everything needed to become a world power. They had vast natural resources, an industrious and hard-working population, and a government established on principles of liberty and equality. That said, it is important to understand that the emergence of the United States as a world power was a process; it didn't happen over night. It took place over the course of decades throughout the late 19th century.

The transformation of America into a world power took place gradually throughout the late 19th century.

Not all historians chart the growth of the United States in the same way. Because of this, not everyone agrees on when exactly the U.S. became a world power. Furthermore, the term 'world power' is somewhat subjective, depending on how that term is defined. After all, what exactly does it mean to be a 'world power'? Does it depend on the size of a country's military? Economy? Global expansion? Achievements? It's a complex issue that we will try to address briefly.

Development of the U.S. as a World Power

So from the beginning, the United States was the major power in the Western Hemisphere. After the War of 1812, British involvement in the Western Hemisphere began to decline. The American infrastructure grew by leaps and bounds during the first half of the 19th century, thanks to the American Industrial Revolution. As a result of the Mexican-American War (1846-1848), Mexico was forced to give to the U.S. what is now the American Southwest. Then there was that messy Civil War, even after which the U.S. showed little interest in global expansion. The American army was only one-twentieth the size of France or Great Britain's. Hardly a global power!

However, by the late 19th century, interest in global expansion began to increase. An assertive foreign policy stance began to characterize the U.S. In 1898, the U.S. annexed Hawaii. That same year, the Spanish-American War broke out, with the United States emerging victorious over Spain. As a result, the U.S. gained control over Cuba, Puerto Rico, Guam, and the Philippines. The late 19th century can be considered the Age of American Imperialism. Imperialism is the act of extending a county's authority upon other nations or regions. Basically, it's a nicer way of saying 'take over,' as in 'we're going to take over your country.'

This 1898 political cartoon symbolizes American imperialism throughout the Western Hemisphere.

America was largely isolationist prior to the late 19th century. The Age of American Imperialism marked a turning point, in which the U.S. took a more interventionist approach toward foreign policy. Theodore Roosevelt was instrumental in this change, both in his role as Assistant Secretary of the Navy and as President. As President, he commissioned the Great White Fleet, a collection of American warships, to circumnavigate the globe between 1907-1909. This act was symbolic because it was a way for the U.S. to tell the world: 'Hey, look how mighty we are!'

The Great White Fleet at sea in 1907.
Great White

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