Nothing wise, we hear, about pacifist showing mawkishness (5-5)
I believe the answer is:
lovey-dovey
'nothing wise' is the definition.
The definition suggests an adjective which matches the answer.
'we hear about pacifist showing mawkishness' is the wordplay.
I cannot quite see how this works, but
'pacifist' could be 'dove' (dove is a kind of pacifist) and 'dove' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for lovey-dovey that I've seen is " Overly affectionate?".)