In USA, cryptic clues man solved (5,3)

I believe the answer is:

uncle sam

I'm a little stuck... Click here to teach me more about this clue!

'in usa' is the definition.
'uncle sam' can be an answer for 'usa' (I've seen this before). I'm unsure of the 'in' bit.

'cryptic clues man solved' is the wordplay.
'cryptic' indicates an anagram (a cryptic or obscure order of the letters).
'man' becomes 'N' (knight, a man in chess).
'solved' becomes 'am' (I can't justify this - if you can you should give a lot more credence to this answer).
'clues'+'n'='cluesn'
'cluesn' with letters rearranged gives 'uncles'.
'uncles'+'am'='UNCLE SAM'

Can you help me to learn more?

(Other definitions for uncle sam that I've seen before include "Personification of the States" , "America as a recruiting officer" , "Avuncular appellation for USA" , "Personification of USA" , "Iconic male relative for America" .)

I've seen this clue in the Sydney Morning Herald.

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