Diplomacy means freedom (10)
I believe the answer is:
discretion
This clue is a double definition.
'diplomacy' is the first definition.
(thesaurus)
'freedom' is the second definition.
(discretion is a kind of freedom)
'means' acts as a link.
(Other definitions for discretion that I've seen before include "Diplomacy" , "Tact - prudence" , "Tactful quality" , "Liberty to act at pleasure; prudence" , "The better part of valour" .)