From the Age of Extremes to a World Power: Introduction
The Industrial Revolution with its technological advancements and the land expansion of the United States were signs of a growing nation. America entered a golden age of both extreme wealth and extreme poverty. The American melting pot theory took hold as millions of immigrants began their lives in American cities during a second wave of mass immigration. Large numbers of African-Americans also migrated to Northern industrial cities in search of opportunities away from the Jim Crow South. During this time, the United States also began to develop an imperialistic attitude and land held by other countries became attractive. It was time for the country to branch out as well as defend interests abroad.
