Insulted a British and American journalist (6)
I believe the answer is:
abused
'insulted' is the definition.
('abused' can be similar in meaning to 'insulted')
'a british and american journalist' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'and' says to put letters next to each other.
'american' becomes 'us'.
'journalist' becomes 'ed' (short for editor).
'a'+'b'+'us'+'ed'='ABUSED'
(Other definitions for abused that I've seen before include "Reviled or misused" , "vilified" , "Made improper use of" , "Wrongfully treated" , "Criminally maltreated" .)