Copper embargo for islander? (5)
I believe the answer is:
'islander?' is the definition.
(I've seen this before)
'copper embargo' is the wordplay.
'copper' becomes 'Cu' (chemical symbol).
'embargo' becomes 'ban' (a ban on trade).
'for' acts as a link.
(Other definitions for cuban that I've seen before include "Like Fidel Castro" , "Kind of high quality cigar" , "Caribbean" , "from island republic" , "islander" .)