Answer: Isolationism
Explanation:
Isolationism is referred to a form of foreign policies incorporated by leaders by keeping the distance to the affairs of other countries, at their nation best interests.
Isolationism policy was adopted by European countries (such as Germany and Italy) when the world is experiencing depression after the world war.
This policy led some European countries into territorialism, a system of government in which the government takes absolute control of their citizens’ lives. Thus, this led to the major economic and political instability in the European countries.