Journalists initially unhappy about force (8)
I believe the answer is:
pressure
'force' is the definition.
(I know that force can be written as pressure)
'journalists initially unhappy about' is the wordplay.
'journalists' becomes 'press' (the press can mean the newspaper industry).
'initially' indicates taking the first letters.
'about' becomes 're' (regarding).
The first letter of 'unhappy' is 'u'.
'press'+'u'+'re'='PRESSURE'
(Other definitions for pressure that I've seen before include "Coercion, intimidation" , "Stressful urgency" , "Force measured in pascals" , "Coercion or forceful persuasion" , "tension" .)