Display resistance then help strike (3-4)

I believe the answer is:

air-raid

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'display resistance then help strike' is the definition.
I can't tell whether this definition defines the answer.

'display resistance then help' is the wordplay.
'display' becomes 'air' (I've seen this in another clue).
'resistance' becomes 'r' (electronics abbreviation).
'then help' becomes 'aid' (synonyms. I am not sure about the 'then' bit.).
'air'+'r'+'aid'='AIR-RAID'

Can you help me to learn more?

I've seen this clue in The Telegraph.

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