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siege mentality

noun
  1. a state of mind whereby one believes that one is being constantly attacked, oppressed, or isolated.

Origin of siege mentality

First recorded in 1965–70
Also called bun·ker men·tal·i·ty.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for siege mentality

siege mentality

noun
  1. a state of mind in which a person believes that he or she is being constantly oppressed or attacked
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012