Militia's price set, favouring expansion (13)

I believe the answer is:

imperialistic

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'favouring expansion' is the definition.
I can't tell whether this definition defines the answer.

'militia's price set' is the wordplay.
'set' indicates anagramming the letters (instruction to set the letters).
'militias'+'price'='militiasprice'
'militiasprice' with letters rearranged gives 'IMPERIALISTIC'.

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(Another definition for imperialistic that I've seen is " Expansionist".)

I've seen this clue in The Daily Express.

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