Enforced change of leadership after troops get back (6)
I believe the answer is:
recoup
'get back' is the definition.
(as in recouping funds)
'enforced change of leadership after troops' is the wordplay.
'enforced change of leadership' becomes 'coup' (as in a coup d'etat).
'after' means one lot of letters go next to another.
'troops' becomes 'RE' (Royal Engineers army regiment).
'coup' put after 're' is 'RECOUP'.
(Other definitions for recoup that I've seen before include "Regain (expenditure)" , "Regain a loss through subsequent profits" , "Get back one's losses" , "Get back again, say losses (6)" , "Reimburse or compensate" .)