Isolationism in general is a national foreign policy of detachment from other nations, as opposed to interventionism. Most often it refers to the foreign policy of the United States of America from the formation of the Monroe Doctrine to about World War II. During this time, U.S. policymakers refrained from actively engaging in the affairs of other major powers, particularly those in Europe, to the point that U.S. entry into both World Wars occurred long after each war began. However, because the United States had been actively interventionist in the affairs of its Latin American neighbors during this period, the term "isolationist" is somewhat misleading.
Following World War II, American policymakers took an active interest in global foreign affairs, becoming heavily interventionist in parts of the world outside of its traditional involvement in the Western Hemisphere.
The isolationist policy of the United States has been widely criticized by other countries such as France and Germany, while an interventionist policy by the United States has been criticized particularly by highly populated Muslim countries such as those in the Middle East.