Can holy wars be peaceful? (7)
I believe the answer is:
halcyon
'peaceful?' is the definition.
(I've seen this before)
'can holy wars' is the wordplay.
'wars' indicates an anagram (I've seen 'warring' mean this).
'can'+'holy'='canholy'
'canholy' is an anagram of 'HALCYON'.
'be' acts as a link.
(Other definitions for halcyon that I've seen before include "Idyllically happy and peaceful" , "Tropical kingfisher" , "Such days are calm and happy" , "Idyllic" , "Of a period, happy and peaceful - say youth" .)