Ineffective person with island politician (4)
I believe the answer is:
wimp
'ineffective person' is the definition.
(I've seen this before)
'with island politician' is the wordplay.
'with' becomes 'w' (abbreviation).
'island' becomes 'i'.
'politician' becomes 'mp'.
'w'+'i'+'mp'='WIMP'
(Other definitions for wimp that I've seen before include "Softie" , "Namby-pamby" , "A weak ineffectual man" , "Spineless man" , "Feeble or ineffective man" .)