Old secret police force’s lack of action (6)
I believe the answer is:
stasis
'action' is the definition.
The answer and definition can be both states of affairs as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'old secret police force's lack of' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'secret police' becomes 'stasi' (state security service of the GDR, East Germany).
'force's' becomes 'F's' (symbol used in Physics e.g. f=ma).
'lack' is a deletion indicator.
'o'+'stasi'+'fs'='ostasifs'
'ostasifs' with 'of' taken away is 'STASIS'.
Can you help me to learn more?
(Other definitions for stasis that I've seen before include "State in which blood-flow is stopped" , "Stoppage of circulation or stagnation" , "Cessation" , "Inactivity or stoppage of circulation" , "No progressive state" .)