The Monroe Doctrine simply stated that the west will not interfere with the affairs of Europe as long as they didn't interfere with us. This enabled us to be able to deal with the smaller countries and help them reform their government. The Monroe doctrine allowed the United States to become "protectors" of the smaller countries in the western hemisphere.
a. prairie farmers, a group who mostly opposed the railroad b. government regulations protecting the environment c. Native American raids on work camps.