The Roosevelt Corollary (1904) to the Monroe Doctrine proclaimed the right o the United States to 1. intervene in the internal affairs of Latin American nations. The Corollary was to the earlier Monroe Doctrine, which told European powers to stay our of Western Hemispheric affairs. Roosevelt's reasoning was that the United States would have to intervene were Latin American countries to weak to provide funds or infrastructure necessary for the support of trade. If those countries could not support trade, the US would have to intervene because a failure of trade would, purportedly, negatively affect the US's ability to manage the affairs of the region.