Occupation of Japan

The Allied occupation of Japan after World War II was mainly by the United States, with support from the British Commonwealth. It lasted between 1945–1952, ending after the 1951 San Francisco Peace Treaty.

The occupation, and the occupation of West Germany, created liberal democratic countries. These occupations, and the democratic peace theory, have been inspirations for various later wars and occupations, such as the Iraq War, with liberal democracy anticipated to be similarly installed.

This ignores the advantages Germany and Japan had, with high average country IQ and low ethnic heterogeneity. See the Democracy article.