Military doctrine, merely crude when raised (4,3)

I believe the answer is:

just war

'military doctrine' is the definition.
(doctrine of a war which is morally justifiable)

'merely crude when raised' is the wordplay.
'merely' becomes 'just' (synonyms).
'crude' becomes 'raw' (synonyms).
'when raised' is a reversal indicator (in a down clue, letters go up).
'raw' backwards is 'war'.
'just'+'war'='JUST WAR'

I've seen this clue in The Guardian.

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