Tolerated Henry being destructive (6)
I believe the answer is:
lethal
'destructive' is the definition.
(I've seen this before)
'tolerated henry' is the wordplay.
'tolerated' becomes 'let' (tolerate can mean to let something happen).
'henry' becomes 'hal' (short for Henry).
'let'+'hal'='LETHAL'
'being' is the link.
(Other definitions for lethal that I've seen before include "Enough to cause death" , "Able to cause death" , "Deadly or mortal" , "Death-dealing" , "Noxious" .)