No tears, perhaps for betrayal (7)
I believe the answer is:
'for betrayal' is the definition.
'no tears perhaps' is the wordplay.
'perhaps' indicates anagramming the letters.
'notears' with letters rearranged gives 'TREASON'.
(Other definitions for treason that I've seen before include "Serious crime" , "Betrayal of one's nation" , "Lese-majesty" , "Senator (anag)" , "Stare on (anag.)" .)