1974 4 Dec. iv.12/7 The inertia of the bunker mentality had taken over.
1981 J. W. Cooper & M. H. Novak 227 Is there not a danger that you are developing a bit of a bunker mentality here about the state of siege of capitalism?
2004 6 Jan. i. 17/7 Faced with competition from women the reaction has been to hunker down in a bunker mentality.