In the nineteenth century, a few different environmental matters became topics of public debate. By this time, America's expansion into the West and increasingly rapid industrialization had seriously depleted natural resources, particularly lumber. As a result, many people began to advocate for the preservation of these vital resources, sparking an environmental movement. Various organizations also saw the way America's natural beauty was suffering as a result of deforestation and argued that the wilderness should be protected. Finally, as industrialization continued, America's urban centers also became centers of pollution, and there were calls to improve air quality and control pollution.
These big topics of debate likely came about because conservationists were worried about America's attitude toward natural resources; essentially, people were using them and therefore depleting them without understanding or caring what kind of impact that would have in the future. For example, there were people who saw the wilderness as a wasteland ready to be developed and cleared, and others who believed that it was a romantic escape from the bustle of civilization and a perfect example of America's natural beauty. At the turn of the twentieth century, President Theodore Roosevelt took office and took conservationists' worries seriously, establishing the United States Forest Service, several national parks, and many national monuments.