At the turn of the nineteenth century into the twentieth century, the United States had actively practiced expansionism on a worldwide scale. The US became involved with foreign affairs and international issue as never before. In a short period of time, our interests outside of the national borders were expanded significantly. And although the US tried to back them up with humanitarian reasons, the heart of them lied in imperialism. The United States wanted to become the world's superpower in the area of politics, economy and land surface.
The US expanded its interests internationally in politics because of all that was going on at the time. Europe and Russia started claiming lands in Africa and Asia, respectively. These nations badly treated the conquered people and their cultures. The US became involved by creating the Open Door Policy that required a respect and toleration of all nations, especially the Chinese. However, under this humanitarian cause lay the imperialistic reason. The US simply did not want other country to step into China, where they themselves could benefit a lot. The US wanted to promote democracy and stabilize all the nations. They also could not stand idle and witness foreign nations increasing their power through new land annexations. That would create a potential threat that US could not tolerate. So in addition to ODP, the president created the Roosevelt Coronary. This document gave an official right to the US to intervene with issues concerning Latin America. This move was explained by that a nation of a great ability, such as the US, had to help smaller nations in need. In reality though, the US became involved, because they were afraid that if Europe steeped in to South America, it might just as well go for the Northern one, too. The more policies that US created, the more authority it was actually granting itself, and that signifies the move toward imperialism.