Coming from the south, one's goal to make US city (5)
I believe the answer is:
miami
'us city' is the definition.
(I've seen this before)
'coming from the south one's goal' is the wordplay.
'coming from the south' says the letters should be written in reverse (in a down clue, letters go up).
'one's' becomes 'im' ('one is' is a formal way of saying 'I am').
'goal' becomes 'aim' (aim is a kind of goal).
'im'+'aim'='imaim'
'imaim' in reverse letter order is 'MIAMI'.
'to make' is the link.
(Other definitions for miami that I've seen before include "Florida resort city, Beach" , "Floridian city" , "Port in Florida" , "Popular sun-city of Florida" , "tourist centre" .)