Answer :
Pursuing a policy of isolationism is a policy in which a country decides not to interfere or engage in the affairs of other nations, of these examples the United States declining to give aid to Hungarian patriots in 1849 is an example of isolationism. Imperialism is the policy of acquiring territory or establishing a colony, the United States annexation of Samoa in 1899 or of Hawaii in 1900 would be examples of American imperialism. The final example of intervention is when a nation decides to interfere in the affairs of another nation through force often or coercion and a strong example of this was the United States proposal of the Open Door Policy of 1899 which sought to control the Chinese market and the Chinese economic decision making in regards to trading partners.