Fail to get great deal that would assist higher aims? (9)

I believe the answer is:

bombsight

'that would assist higher aims?' is the definition.
(a bombsight helps aim bombs)

'fail to get great deal' is the wordplay.
'fail' becomes 'bomb' (synonyms).
'to get' says to put letters next to each other.
'great deal' becomes 'sight' (synonyms).
'bomb'+'sight'='BOMBSIGHT'

(Another definition for bombsight that I've seen is " Aircraft's aiming device".)

I've seen this clue in The Times.

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