<span>Imperialism would make the United States economically competitive with other nations</span>
American settlers continue to spread to the west and took land from Native Americans. As expansion continued, agreements were signed and they were broken with native americans losing their homes and land and force to move west. As Native Americans were forced to more to the west, they are not able to adopt to the environment they are moving to, so they died due to lack of food or diseases.
The demand quantity will increase due to more of them being bought.