Insular

Literally, of or pertaining to an island, but usually used to describe the mindset of one who does not know and does not wish to know of matters outside one's existing experience (ie metaphorically one's island) or to give those matters credit. An example would be a person or persons who do not wish to know of matters outside their own country, religion or political viewpoint. See Wilful Ignorance and [Conservapedia]