The Roosevelt Corollary was an addition to the Monroe Doctrine. The Monroe Doctrine of 1823 requested that Europe not claim any further colonies in the Western Hemisphere. The Roosevelt Corollary of 1904 asserted that the United States would interfere in case of conflict in Latin America, rather than Europe sending in troops.
Theodore Roosevelt issued the Roosevelt Corollary in response to growing fears of a conflict between European countries and Venezuela. It stated that the United States would step in if any Latin American nation failed to pay debts or engaged in civil unrest. It also asserted that Europe would not have policing power on Latin American nations. Roosevelt's goal was to protect the Americas as a whole and maintain peace internationally, because the Monroe Doctrine had not been assertive enough.