Drop most celebrated advocate of worldwide policy (9)

I believe the answer is:

globalist

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

'drop most celebrated advocate' is the definition.
The definition suggests a singular noun which matches the answer.

'worldwide policy' is the wordplay.
'worldwide' becomes 'global' (synonyms).
'policy' becomes 'ist' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'global'+'ist'='GLOBALIST'

'of' is the link.

Can you help me to learn more?

I've seen this clue in The Guardian.

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