In what ways did the United States expand its territory and industries during the 1800s?

The United States enjoyed a period of rapid growth during the nineteenth century. In terms of territory, the United States more than doubled in size with the Louisiana Purchase. The young nation then gained the Southwest and California in a controversial yet successful war against Mexico. The United States then bought a strip of land south of the Gila River in Arizona less than ten years after the end of the Mexican War. The United States settled land disputes with Britain in order to gain clear title to the Oregon Territory and then bought Alaska from the Russians after the Civil War. American sugar and pineapple growers overthrew the rightful queen of Hawaii in order to annex the land for the United States and to have their sugar and pineapple imported duty-free. In another controversial yet successful war, the United States gained Puerto Rico, Guam, and the Philippines from Spain.
Most of these land acquisitions were done under the guise of Manifest Destiny, which was the belief that God chose the American people to rule the North American continent, but many of the land acquisitions also had economic underpinnings, such as the need to acquire mineral wealth and cheaper farmland for a growing population.
Industrially, American factories performed mostly well during this period, with the exception of a few major recessions that were mainly caused by factory overproduction. The cotton gin made the United States a key player in the textile industry, and Southern cotton powered the economies of the Northeastern United States as well as Britain. Interchangeable parts, also pioneered by Eli Whitney, helped to make American goods cheaper for people all over the world.
The Civil War demonstrated the power of the telegraph and the railroad in supplying soldiers—after the war, railroads become more common and people of the United States started to depend on store-bought goods more than what was traditionally made in the home. The boom in the railroad market as well as the need to create bigger factories and places to house workers made possible a boom in the steel industry—by the turn of the century, U.S. Steel was a household name all over the world. The need for workers to work longer hours led to the rise of the kerosene lamp, later to be replaced by electricity.
All of these things in industry were powered by American innovators such as Carnegie, Rockefeller, and Edison. While most Americans did not get rich from the industrialization of the nation, most Americans did at least receive some of the benefit of the new consumer goods produced by the United States.