Support simple military command (5,4)

I believe the answer is:

stand easy

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'military command' is the definition.
I know nothing about this answer so I can't tell whether this works.

'support simple' is the wordplay.
'support' becomes 'stand' (stand is a kind of support).
'simple' becomes 'easy' (similar in meaning).
'stand'+'easy'='STAND EASY'

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(Another definition for stand easy that I've seen is " Soldiers thus ordered".)

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

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