兵出须名 (兵出須名) bīngchū xū míng

bīngchū xū míng phrase had to give their military expeditions justification
Domain: Idiom 成语
Notes: Quote: from “The Literary Mind and the Carving of Dragons” (Amies 2021 tr.; see also tr. by Liu, Xie and Youzhong Shi tr. 2015, Kindle Ed., ch. 20)