President James Monroe's State of the Union address in 1823 included a significant change to United States foreign policy which later became known as the Monroe Doctrine. In a key addition to this policy called the Roosevelt Corollary, the United States reserved the right to intervene in any nation of the Western Hemisphere it determined to be engaged in "chronic wrongdoing". This new expansionism coupled with the loss of relative power by the colonial nations enabled the United States to become a major influence in the region. In the early part of the twentieth century this influence was extended by participation in The Banana Wars. Areas outside British or French control became known in Europe as "America's tropical empire".