Ignorance of or lack of interest in cultures, ideas, or peoples outside one’s own experience. (Oxford Dictionaries)
The quality of only being interested in your own country or group and not being willing to accept different or foreign ideas. (Cambridge Dictionary)
The noun insularity refers to the quality of being isolated or detached. In fact, the word is based on the Latin word insula, for “island.” (Vocabulary.com)
Cultural insularity is the norm.
Our Brexit blog.
This Is How We Will Beat The New Insularity — The Cosmopolitan Embrace Of Migration