In NATO's disarray, they aren't all united (7)

I believe the answer is:

nations

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'they aren't all united' is the definition.
The definition suggests an adverb but the answer is not.

'in nato's disarray' is the wordplay.
'disarray' indicates anagramming the letters.
'in'+'natos'='innatos'
'innatos' anagrammed gives 'NATIONS'.

Can you help me to learn more?

(Other definitions for nations that I've seen before include "No stain (anag.)" , "Countries" .)

I've seen this clue in the Evening Standard.

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