There is no doctrinal statement in American diplomatic history that is more fundamental than the Monroe Doctrine. It was designed to draw a strategic line between the New World and the Old, and to alert the European powers that their political influence and presence was no longer welcome in the Western Hemisphere. No doctrinal statement has been enforced as often as the Monroe Doctrine, which has been used to justify U.S. intervention throughout Central America and the Caribbean. The Monroe Doctrine was cited in the Bay of Pigs invasion of Cuba in 1961, a perfect failure, as well as the Cuban missile crisis, a diplomatic triumph.