Raid loses nothing for conflict (4)
I believe the answer is:
fray
'for conflict' is the definition.
(fray is a kind of conflict)
'raid loses nothing' is the wordplay.
'raid' becomes 'foray' (synonyms).
'loses' indicates named letters should be taken away.
'nothing' becomes 'O' (O resembles 0).
'foray' with 'o' taken away is 'FRAY'.
(Other definitions for fray that I've seen before include "Wear away at the edges" , "Unravel; battle" , "Wear away from rubbing" , "Disturbance" , "Ravel" .)