Part of Vietnam a G.I. called enchanting (7)
I believe the answer is:
magical
'enchanting' is the definition.
(I've seen this before)
'part of vietnam a g i called' is the wordplay.
'part of' says the answer is hidden in the clue.
'MAGICAL' is hidden in the letters of 'vietnam a g i called'.
(Other definitions for magical that I've seen before include "Bewitching" , "tricky?" , "Mysterious, enchanting" , "Charming" , "Enchanted" .)