A song for one involved in ritual banner-waving (4,9)

I believe the answer is:

rule britannia

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(Other definitions for rule britannia that I've seen before include "Arne patriotic song" , "Britons never slaves song" , "Patriotic British song" , "Thomas Arne's patriotic composition" , "Regular Last Night of the Proms number" .)

I've seen this clue in The Irish Independent.

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