For example, the fall of US spy state is so nuanced from the start (6)
I believe the answer is:
season
'for example the fall of us spy' is the definition.
I can't judge whether this definition defines the answer.
'state is so nuanced from the start' is the wordplay.
'state' becomes 'sea' (I am not sure about this - if you are sure you should believe this answer much more).
'from the start' suggests taking the first letters.
The initial letter of 'nuanced' is 'n'.
'sea'+'so'+'n'='SEASON'
Can you help me to learn more?
(Other definitions for season that I've seen before include "To dry (wood) for use as timber" , "Major division of year characterised by weather and growth" , "Add flavour with salt and pepper" , "instruction in recipe" , "temper" .)