ideologically inbred
adj.— «College towns have cosmopolitan amenities (lectures, music, ethnic restaurants, libraries) but also an almost surreal degree of cultural cohesion—“ideologically inbred” communities where residents read, watch and vote for the same things, in the view of Bill Bishop, author of “The Big Sort: Why the Clustering of Like-Minded America Is Tearing Us Apart,” published in May.» —“Towns They Don’t Want to Leave” by Rachel Aviv New York TImes July 27, 2008. (source: Double-Tongued Dictionary)