Soldier debriefed after going? (8)

I believe the answer is:

commando

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'soldier' is the definition.
(I know that commando is a type of soldier)

I don't understand the remainder of the clue.

(Other definitions for commando that I've seen before include "Soldier trained for carrying out raids" , "Soldier from elite unit" , "Military raider" , "Member of a special service military unit" , "Specialist soldier" .)

I've seen this clue in The Irish Times.

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