Family businesses and small artisan shops provided the main means of employment before the Industrial Revolution, after which urban-area factories became a dominant economic and social force. Because factories attracted large numbers of domestic and immigrant laborers, they were able to grow rapidly in size and scope. Immigration became a major social revolution precipitated by the Industrial Revolution, dramatically altering the ethnic, social, economic, and political landscape of the United States. The owners of America's new industries, from textiles to steel, became known as robber-barons due to their ruthless business practices. A laissez-faire government permitted big business to flourish, and the big business barons retained significant political clout because of their economic power. Men like Carnegie, Gould, Rockefeller, and Vanderbilt built massive fortunes, creating a new type of American aristocracy and an unprecedented level of wealth. The laissez-faire politics in vogue around the turn of the century increased the production capabilities of robber-baron companies and thereby stimulated industrial growth. Moreover, laissez-faire policies remain central to the American capitalist system still in place in the 21st century.

However, laissez-faire government policy and the ruthless pursuit of profit meant little regard for the rights of workers. Child labor was common in the late nineteenth-century, as were deplorably dangerous working conditions and low wages. The labor movement raged in the United States by the turn of the century, requiring a major shift in public policy and labor...

The fruits of the labor movement would not be fully realized until well after 1900.
The triumph of the robber baron, the blossoming of new technologies, and the rapid growth of American cities meant that the United States had become the world's leading industrial power by the start of the 20th century. An extensive network of railroads permitted the nation's factories to ship goods over long distances: from the East Coast to the West. The nation became more unified and cohesive as a result of the railroads, and local economies became more interdependent. Westward expansion meant that the scores of Americans who pioneered across the plains did not have to worry about starting a family farm. The necessities of life: food, shelter, and clothing, could all be manufactured and produced elsewhere and shipped via the railroads. Less dependence on subsistence farming also meant more time could be devoted to the production of large quantities of marketable goods and services. The combination of technological innovations, lack of governmental regulation, and urbanization propelled America to economic dominance.