Consequence of Royal Engineers striking? (12)
I believe the answer is:
repercussion
'consequence' is the definition.
(I know that repercussion is a type of consequence)
'royal engineers striking?' is the wordplay.
'royal engineers' becomes 'RE' (abbreviation).
'striking?' becomes 'percussion' (I've seen this before).
're'+'percussion'='REPERCUSSION'
'of' acts as a link.
(Other definitions for repercussion that I've seen before include "Backlash" , "Impact" , "Recoil; reverberation" , "Unintended consequence" , "Indirect consequence of some action" .)