Worried the Pentagon is educating insiders (8)
I believe the answer is:
agonised
'worried' is the definition.
(to agonise is to worry or fret)
'pentagon is educating insiders' is the wordplay.
'AGONISED' is hidden in amongst the letters.
However, I'm uncertain how the hidden word is indicated.
'the' is the link.
Can you help me to learn more?
(Other definitions for agonised that I've seen before include "Felt mental anguish (over a decision)" , "San Diego (anag) - worried intensely" , "Tormented" , "suffered torment" , "Suffered mentally in San Diego" .)