Broadcast skirmish, so touch up pictures (8)
I believe the answer is:
'touch up pictures' is the definition.
(airbrush can mean to improve a photograph)
'broadcast skirmish' is the wordplay.
'broadcast' becomes 'air' (to air on TV).
'skirmish' becomes 'brush' (synonyms).
'so' is the link.
(Other definitions for airbrush that I've seen before include "Doctor photographs etc" , "Improve the image" , "Sort of spray" , "change photo?" , "Prettify - alter a photo" .)