Trooped out to destroy... (7)
I believe the answer is:
torpedo
'destroy' is the definition.
(I've seen this before)
'trooped out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'trooped' is an anagram of 'TORPEDO'.
'to' is the link.
(Other definitions for torpedo that I've seen before include "Self-propelled marine weapon" , "Poor Ted (anag)" , "ruin" , "Self-propelled submarine weapon" , "Sub's missile" .)