America supports strike on Prince Edward Island (9)
I believe the answer is:
lampedusa
'island' is the definition.
(I know that Lampedusa is a island)
'america supports strike on prince edward' is the wordplay.
'america' becomes 'usa' (synonyms).
'supports' means one lot of letters go next to another (bottom letters provide a support for the top ones).
'strike on prince edward' becomes 'lamped' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'usa' put after 'lamped' is 'LAMPEDUSA'.
Can you help me to learn more?
(Other definitions for lampedusa that I've seen before include "Italian Med island, mud, sea, pal (anag.)" , "Mediterranean island" .)