'This war's over!' — that fake article by nuclear project (9)
I believe the answer is:
manhattan
'nuclear project' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
'this war's over that fake article' is the wordplay.
'this war' becomes 'nam' (informal term for the Vietnam War).
'over' says the letters should be written in reverse.
'fake' indicates anagramming the letters.
'article' becomes 'an' (indefinite article).
'nam' reversed gives 'man'.
'that' with letters rearranged gives 'hatt'.
'man'+'hatt'+'an'='MANHATTAN'
'by' acts as a link.
Can you help me to learn more?
(Other definitions for manhattan that I've seen before include "New York City borough" , "Cocktail consisting of whisky, vermouth and bitters" , "NY borough" , "area of New York City" , "It blended with spirit" .)