Monroe Doctrine
The Monroe Doctrine was a United States foreign policy implemented by President James Monroe in 1823. It warned European nations against further colonization of the Western Hemisphere, stating that failure to abide by this policy would be reciprocated by direct U.S intervention. While the U.S in the early 19th century certainly lacked the authority to impose their policy on the more powerful European nations, Britain like-mindedly wanted to keep all European nations out of the Western Hemisphere to maintain their superior national status, as they had the authority to keep the other European powers in line.
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