When the United States Steel Corporation was created in 1902, it was the largest corporation America had known up to that time. It produced twice as much steel as all of its domestic competitors put together. Today, the United States Steel Corporation produces about 20 percent of the steel that is made in this country. Today, domestic competitors produce more than three times as much steel as does the United States Steel Corporation.

United States Steel Corporation is a steel producer company created in 1901 by J. P. Morgan and Elbert H. Gary, from the fusion of several steel mills, which enabled its CEO, Andrew Carnegie, to increase its market share in the United States from 10% to 30% from 1880 to 1900.

With industrialization following the Civil War, the growth in steel demand increased eightfold from 1880 to 1900, reaching 10 million tonnes, making the United States the world's largest producer. Over the next thirteen years this production tripled. In 1913, they produced as much as Germany, the United Kingdom and France combined.

The importance of US Steel only increased during the twentieth century. In 1980, a year before the inauguration of Ronald Reagan, it was the largest integrated steel production company in the United States, employing 120,000 workers. However, during the 1980s, automation, along the lines of large Japanese companies, led to a number of layoffs: ten years later, around 20,000 employees were enough to achieve the same result.