The Monroe Doctrine was a speech given by President James Monroe in December 1823. A doctrine is a rule or principle, so the title means Monroe’s principle. This principle states that the United States promises to respect any colonies already held by European powers in the Americas but will not permit any new colonies to be taken. In return the United States promises not to seek any colonies in Europe. At the time the U.S. was a weak nation and the doctrine was largely ignored. Later, however, when the U.S. became a world power, it was used to prevent European nations from taking over countries in Latin America.