Corrupt cadre infiltrating Guantanamo rally (6)

I believe the answer is:

amoral

I'm a little stuck... Click here to teach me more about this clue!

'corrupt cadre' is the definition.
'amoral' can be an answer for 'corrupt' (thesaurus). I'm not certain of the 'cadre' bit.

'infiltrating guantanamo rally' is the wordplay.
'infiltrating' indicates the answer is hidden within the clue.
'AMORAL' can be found hidden inside 'guantanamo rally'.

Can you help me to learn more?

(Other definitions for amoral that I've seen before include "Without ethics" , "Lacking any ethical standards" , "Unprincipled" , "Unaffected by any sense of right and wrong" , "Lacking sense of decency" .)

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

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