Idiot's taken in twice about countryman (8)
I believe the answer is:
moroccan
'countryman' is the definition.
(someone from Morocco)
'idiot's taken in twice about' is the wordplay.
'idiot' becomes 'moron' (synonyms).
'taken' indicates putting letters inside.
'in twice' becomes 'acc' (I can't justify this - if you can you should believe this answer much more).
'about' shows that the letters should be reversed in order.
'acc' reversed gives 'cca'.
'moron' going around 'cca' is 'MOROCCAN'.
(Other definitions for moroccan that I've seen before include "From Casablanca, perhaps?" , "Native of Casablanca" , "north African" .)