State of Carolina if reformed (10)
I believe the answer is:
california
'state' is the definition.
(I know that California is a American state)
'carolina if reformed' is the wordplay.
'reformed' indicates anagramming the letters.
'carolina'+'if'='carolinaif'
'carolinaif' anagrammed gives 'CALIFORNIA'.
'of' is the link.
(Other definitions for california that I've seen before include "US state" , "The Golden State" .)