Offensive criticism (6)
I believe the answer is:
attack
I believe this is a double definition.
'offensive' is the first definition.
(an attack is a military offensive)
'criticism' is the second definition.
(I know that attack is a type of criticism)
(Other definitions for attack that I've seen before include "Assault, offensive" , "Act violently against or criticise strongly" , "Offensive move" , "mount an offensive" , "Set upon" .)