Policeman carries little British idiots across the pond (6)
I believe the answer is:
dweebs
'idiots across the pond' is the definition.
(insulting US term)
'policeman carries little british' is the wordplay.
'policeman' becomes 'ds' (abbreviation for Detective Sergeant).
'carries' means one lot of letters goes inside another (inserted letters carried inside).
'little' becomes 'wee' (similar in meaning).
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'wee'+'b'='weeb'
'ds' going around 'weeb' is 'DWEEBS'.
(Other definitions for dweebs that I've seen before include "They're socially inept!" , "nerds" .)