Answer:
The policy of remaining separate from the affairs of other countries or groups is called isolationism.
Step-by-step explanation:
Isolationism is the political tendency of a people or nation to turn away from the world outside of them. It usually happens from fear of being dominated from a cultural, military or economic point of view, or on the contrary from turning away from that perceived threat. Autarky is the goal as a means to maintain isolationism.
In a different context, isolationism can also mean that a country does not interfere with the affairs of other countries without a country actually separating itself from the rest of the world (a kind of non-interventionism). Switzerland can be mentioned as an example of this.