Crazy military commander leaves African island in trauma (4)

I believe the answer is:

scar

'trauma' is the definition.

I cannot understand how the rest of the clue works.

(Other definitions for scar that I've seen before include "reminder of sword-fight?" , "A bare precipice" , "It shows where wound was" , "Evidence of a past injury?" , "Craggy rock formation" .)

I've seen this clue in The Independent.

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