Cover for American gangster (4)
I believe this clue is a double definition.
'cover' is the first definition.
(hooding is a kind of covering)
'american gangster' is the second definition.
(I've seen this before)
'for' acts as a link.
(Other definitions for hood that I've seen before include "Head covering or American car bonnet", "this could provide cover", "Cowl -- violent criminal (slang)", "Capital cover", "See 5".)